<Tr> <Th> 49 </Th> <Td> 18 </Td> <Td> "In The Cards" </Td> <Td> Steve DiMarco </Td> <Td> Heather Conkie </Td> <Td> March 28, 2010 (2010 - 03 - 28) </Td> <Td> 318 </Td> </Tr> <Tr> <Td_colspan="7"> A surprise announcement by Peter throws Lou's wedding plans into disarray while Amy and Ty make difficult decisions about their futures . Amy then gives back their "Promise" ring that Ty gave her, then asks for it back . Lisa is being careful not to interfere with Lou's wedding even when Lou needs her help, making Lou feel responsible for Lisa and Jack changing their minds on the engagement . After his break - up with Ashley, Caleb decides to let her go on the rodeo circuit with him . Amy treats one of the horses of a ring of fire contestant, which causes mixed feelings . Lou and Peter get married . </Td> </Tr> <Table> <Tr> <Th> No . overall </Th> <Th> No. in season </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> Prod . code </Th> </Tr> <Tr> <Th> 50 </Th> <Td> </Td> <Td> "Homecoming" </Td> <Td> Grant Harvey </Td> <Td> Heather Conkie </Td> <Td> September 26, 2010 (2010 - 09 - 26) </Td> <Td> 401 </Td> </Tr> <Tr> <Td_colspan="7"> Ty returns home after an absence of three months but brings a young woman, Blair, whom he says is a friend . Amy is not happy, and Ty is oblivious to why she is mad . Blair kisses Ty, but he doesn't reciprocate her feelings, nor does he tell Amy . In the end, Blair leaves with her boyfriend, with Amy accepting that Ty and Blair are just friends . </Td> </Tr> <Tr> <Th> 51 </Th> <Td> </Td> <Td> "What Dreams May Become" </Td> <Td> Grant Harvey </Td> <Td> Ken Craw </Td> <Td> October 3, 2010 (2010 - 10 - 03) </Td> <Td> 402 </Td> </Tr> <Tr> <Td_colspan="7"> Amy scratches the surface to discover Nick Harwell's problems with his polo horse, Dusty . All of the polo horses get sick, so it is up to Ty and Scott to find the problem . Lou hates Dubai, and Tim is dating his jockey, inviting her to Heartland without telling anyone about their true relationship . Jack and Caleb try to appease Lou by fitting a water system for the horses, but things don't quite go to plan . </Td> </Tr> <Tr> <Th> 52 </Th> <Td> </Td> <Td> "Road Curves" </Td> <Td> Dean Bennett </Td> <Td> Heather Conkie </Td> <Td> October 10, 2010 (2010 - 10 - 10) </Td> <Td> 403 </Td> </Tr> <Tr> <Td_colspan="7"> Amy is angry when Chase comes back and insists on her performing a horse clinic with him . When Amy refuses, Chase puts flyers up all over town advertising their show, and she cannot back out . When the show is over, Chase kisses Amy, who kisses him back but does not reciprocate his feelings . She later tells Ty, who forgives her, but punches Chase when he next sees him . Lisa offers to buy the dude ranch . Mrs Bell and Sugarfoot are run off the road by Chase and Ty comes to their aid . Overhearing Ty's concerns about how he will afford vet school, Mrs Bell offers to become his honourary grandmother and to pay for his education, an offer Ty happily accepts . </Td> </Tr> <Tr> <Th> 53 </Th> <Td> </Td> <Td> "Graduation" </Td> <Td> Dean Bennett </Td> <Td> Mark Haroun </Td> <Td> October 17, 2010 (2010 - 10 - 17) </Td> <Td> 404 </Td> </Tr> <Tr> <Td_colspan="7"> Amy is offered a full scholarship for a equine program . With Lou thinking she is stupid not to take it, Amy has problems choosing, and with the fact she is graduating without her mom there . Badger is back and tries to fight for Mallory . Spartan colicks . Tim and Lisa clash over the price for the dude ranch . Amy decides to take a year off of school . </Td> </Tr> <Tr> <Th> 54 </Th> <Td> 5 </Td> <Td> "Where The Truth Lies" </Td> <Td> John Fawcett </Td> <Td> Susin Nielsen </Td> <Td> October 24, 2010 (2010 - 10 - 24) </Td> <Td> 405 </Td> </Tr> <Tr> <Td_colspan="7"> Amy and Ty convince Sarah, the town hermit, to let them treat her sick horse at Heartland . Badger and Mallory go on an adventure neither of them will soon forget . They get trapped in a mine and Jake saves them . On the Dude Ranch front, Lisa and Lou are not seeing eye to eye, and Peter returns to Heartland . </Td> </Tr> <Tr> <Th> 55 </Th> <Td> 6 </Td> <Td> "Win, Place or Show" </Td> <Td> John Fawcett </Td> <Td> Leila Basen and David Preston </Td> <Td> November 7, 2010 (2010 - 11 - 07) </Td> <Td> 406 </Td> </Tr> <Tr> <Td_colspan="7"> Tim gets Amy to ride Lightning Dexter in a stakes race when he finds out his girlfriend Janice has taken a jockeying position with another owner, Dan, who is also Lisa's ex . Badger rolls into Heartland driving a sweet used car . Ty discovers that the car is stolen . Jake gets help from Jack with driving . Mallory is torn between Jake and Badger . Peter tries to buy his way out of the doghouse with Lou while Caleb buys his way into the poorhouse for Ashley . </Td> </Tr> <Tr> <Th> 56 </Th> <Td> 7 </Td> <Td> "Jackpot!" </Td> <Td> TW Peacocke </Td> <Td> Leila Basen and David Preston </Td> <Td> November 14, 2010 (2010 - 11 - 14) </Td> <Td> 407 </Td> </Tr> <Tr> <Td_colspan="7"> Caleb turns to Kit to partner with him so they can win a team roping jackpot . This sets in motion a series of strange events, which results in some unusual team pairings . Kit and Amy pair up and win . Tim is concerned that Lightning Dexter is starting to cost him a lot of money but is not able to race . When the opportunity comes up to possibly sell the horse, he plots to get the maximum amount of cash . Jack finds himself in a bidding' war' with Lisa against her ex-husband Dan . Mallory and Badger's relationship starts to heat up again, but Mallory wonders if she's picked the right guy when she watches Jake and Jamie . She decides she wants Jake . Ashley's mom buys the land Ashley and Caleb live on . </Td> </Tr> <Tr> <Th> 57 </Th> <Td> 8 </Td> <Td> "One Day" </Td> <Td> TW Peacocke </Td> <Td> Mark Haroun </Td> <Td> November 21, 2010 (2010 - 11 - 21) </Td> <Td> 408 </Td> </Tr> <Tr> <Td_colspan="7"> Amy is hired to do a horse clinic with a group of prisoners . One of them is Joe, an old friend of Ty's . Ashley and Caleb attempt to deal with the new landlord / tenant relationship they now have with Ashley's mom, Val . Meanwhile, Mallory, Jamie, Jake, and Badger go berry picking for Mrs. Bell . Mallory and Badger come to terms with their relationship after an incident where everyone finds out that Jake and Badger are both allergic to bees . Badger leaves . </Td> </Tr> <Tr> <Th> 58 </Th> <Td> 9 </Td> <Td> "Local Hero" </Td> <Td> Grant Harvey </Td> <Td> Leila Basen and David Preston </Td> <Td> December 5, 2010 (2010 - 12 - 05) </Td> <Td> 409 </Td> </Tr> <Tr> <Td_colspan="7"> Ty and Amy find a calf in the woods which leads them to Tim's stolen cattle . Tim convinces the family that they need to take the law into their own hands . But the cattle rescue and subsequent drive has to maneuver a dangerous course when they come face to face with the rustlers who shot Tim two years ago, and Mallory's attempt to be part of the adventure puts her in harm's way . Val's efforts to convince Ashley and Caleb to sign a marriage contract leads to a shocking revelation . They are not legally married . Lou returns home from Dubai, in no mood to answer questions about her marriage or why she isn't with her husband . </Td> </Tr> <Tr> <Th> 59 </Th> <Td> 10 </Td> <Td> "Mood Swings" </Td> <Td> Grant Harvey </Td> <Td> Heather Conkie </Td> <Td> January 2, 2011 (2011 - 01 - 02) </Td> <Td> 410 </Td> </Tr> <Tr> <Td_colspan="7"> Grant and Blair--Ty's travel buddies--return to Heartland . The issue of Blair kissing Ty and deciding not to tell Amy is resolved with Ty and Amy breaking up and Ty leaving Heartland to move in with Caleb and Ashley . Also, Caleb and Ashley have difficulty adjusting to the reality that they aren't legally married . Caleb receives advice from Tim . Mallory's adventure of being locked in the horse trailer and being returned to Heartland by the police is still reverberating . Meanwhile, Lou gets news that will have a huge impact on her and Peter's lives . </Td> </Tr> <Tr> <Th> 60 </Th> <Td> 11 </Td> <Td> "Family Business" </Td> <Td> Francis Damberger </Td> <Td> Ken Craw </Td> <Td> January 9, 2011 (2011 - 01 - 09) </Td> <Td> 411 </Td> </Tr> <Tr> <Td_colspan="7"> Amy fights to keep Lightning Dexter in the family when she learns Tim is putting his horse up for sale in a claiming race . Ty neglects his schoolwork to help Caleb hustle money at a pool hall . Chase Powers gets involved in the Dexter claiming race ordeal and makes things awkward between Amy and Ty . Meanwhile, a pregnant Lou has a great idea for the baby's nursery that doesn't sit well with Jack . Peter has problems of his own as he tries to conduct his company's business from Heartland . Mallory quits her job at Heartland and comes to work at Maggie's . </Td> </Tr> <Tr> <Th> 61 </Th> <Td> 12 </Td> <Td> "Lost Song" </Td> <Td> Francis Damberger </Td> <Td> Heather Conkie </Td> <Td> January 16, 2011 (2011 - 01 - 16) </Td> <Td> 412 </Td> </Tr> <Tr> <Td_colspan="7"> While Lou is having the troops clean out the closet in Marion's old room, preparing to transform it into a nursery, some interesting items are found . A guitar which used to belong to Lyndy--Jack's late wife and Marion's mother--is found and Jack finds something interesting in its case . A trophy for "all - round cowboy" won by Tim in Ponoka two decades ago also gets uncovered . Repairs needed to the trophy prompt Caleb to offer to get it fixed . Jack says the most romantic thing he has ever muttered . And Caleb and Ashley get married again, for real . </Td> </Tr> <Tr> <Th> 62 </Th> <Td> 13 </Td> <Td> "The Road Home" </Td> <Td> Eleanore Lindo </Td> <Td> Mark Haroun </Td> <Td> January 23, 2011 (2011 - 01 - 23) </Td> <Td> 413 </Td> </Tr> <Tr> <Td_colspan="7"> Ty continues down his road of recent confusion, so Jack offers advice . To make a point, Jack does something quite dramatic and it puts Ty in a situation which causes his true nature to step up . Lisa and Lou have words deciding how the Dude Ranch will be run once Lou has her baby, and Lou has some words of wisdom for Amy as well . </Td> </Tr> <Tr> <Th> 63 </Th> <Td> 14 </Td> <Td> "Leap of Faith" </Td> <Td> Eleanore Lindo </Td> <Td> Andrew Wreggitt </Td> <Td> February 13, 2011 (2011 - 02 - 13) </Td> <Td> 414 </Td> </Tr> <Tr> <Td_colspan="7"> Amy helps Stuart Forest, the trainer of the horse that got Amy a ton of hits on Youtube for being a "Miracle Girl". His daughter Rihanna's horse is too much for Rihanna to handle but he won't accept that . Chase tries to help by giving Rihanna a new bit, but she is too eager to make her dad proud and has an accident . Stuart then decides to sue Heartland for negligence . Peter is being sued and is bankrupt . Meanwhile, Jack is trying to persuade Mallory to come back to Heartland and care for Copper . </Td> </Tr> <Tr> <Th> 64 </Th> <Td> 15 </Td> <Td> "The River" </Td> <Td> Chris Potter </Td> <Td> Leila Basen and David Preston </Td> <Td> February 27, 2011 (2011 - 02 - 27) </Td> <Td> 415 </Td> </Tr> <Tr> <Td_colspan="7"> There is a bear hanging around Heartland and getting into things on the farm . Amy is doing her best to put the whole lawsuit thing behind her . When Ty comes to talk to Amy about it, she kisses him and Ty kisses back . While Amy is out for a trail ride, she runs into the bear . Lou is feeling that it is the worst possible time to have a baby . Caleb comes back from him and Ashley's honeymoon by himself, while Ashley is still in Italy . Stuart has a revelation when his daughter tells him that it is his fault that she doesn't want to ride anymore and that she hates him . He decides not to go through with the law suit . Soraya and Chase argue and have disagreements . </Td> </Tr> <Tr> <Th> 65 </Th> <Td> 16 </Td> <Td> "Never Surrender" </Td> <Td> Chris Potter </Td> <Td> Story by: Will Pascoe Teleplay by: Leila Basen, Ken Craw, Mark Haroun and David Preston </Td> <Td> March 6, 2011 (2011 - 03 - 06) </Td> <Td> 416 </Td> </Tr> <Tr> <Td_colspan="7"> Caleb's friend Bryce, a paralyzed military vet and ex-rodeo star, hires Amy to help sell his roping horse . However, Amy sees an opportunity to re-train both horse and rider, though she needs help to convince this cowboy that he can recapture his love for riding despite his injury . Tim shares a misunderstanding with Jack through a lack of communication . Ashley hasn't returned yet and Caleb wonders if Ashley likes Italy more than she likes him . Lou agrees to be Marnie's labour coach, but being around Marnie's rambunctious toddler makes her wonder if she's really cut out for motherhood . </Td> </Tr> <Tr> <Th> 66 </Th> <Td> 17 </Td> <Td> "Burning Down the House" </Td> <Td> Dean Bennett </Td> <Td> Leila Basen and David Preston </Td> <Td> March 13, 2011 (2011 - 03 - 13) </Td> <Td> 417 </Td> </Tr> <Tr> <Td_colspan="7"> Tim and his girlfriend announce that they are selling the ranch and moving to California . But one of Tim's old girlfriends comes back and claims that Tim is the father of her son, Shane, and a paternity test says that he is . Ashley finally comes home . Ty is still having trouble just being friends with Amy . Ashley decides to go to school in British Columbia and Caleb is not sure if to go or to stay . </Td> </Tr> <Tr> <Th> 67 </Th> <Td> 18 </Td> <Td> "Passages" </Td> <Td> Dean Bennett </Td> <Td> Heather Conkie </Td> <Td> March 27, 2011 (2011 - 03 - 27) </Td> <Td> 418 </Td> </Tr> <Tr> <Td_colspan="7"> Amy and Ty work through their trust issues as they train a pair of Clydesdales . Tim is still reeling from the knowledge that Shane is in fact his son but he finds himself bonding with the boy despite himself . Bad feelings resurface between Caleb and Val when he accuses her of manipulating Ashley and her decision to go away to the university . Caleb decides to go with Ashley to British Columbia . Meanwhile, Lou's due date is still three weeks away . Lou goes into labor at home, and Ty and Amy deliver a girl . </Td> </Tr> </Table> <Tr> <Th> No . overall </Th> <Th> No. in season </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> Prod . code </Th> </Tr>

When does lou find out she's pregnant in heartland