<Tr> <Th> 24 </Th> <Td> 11 </Td> <Td> "Starstruck!" </Td> <Td> Dean Bennett </Td> <Td> Leila Basen and David Preston </Td> <Td> January 11, 2009 (2009 - 01 - 11) </Td> <Td> 211 </Td> </Tr> <Tr> <Td_colspan="7"> Hollywood starlet and gossip - rag fodder Mindy Fanshaw arrives at Heartland under the pretext of honing her riding skills, which turn out to be non-existent . Mallory is found hiding in one of the dude ranch cabins, having been aided in her' escape' from the boarding school by Jake . Mallory collects items Mindy has used around Heartland, planning to sell them on eBay so she can repay Jake for the money he spent helping her . Mindy digs into the Ty / Amy / Caleb' triangle', lying to all three about what the others had said and attempts to pit the three against each other . She attacks Amy in particular for being unable to choose between Ty and Caleb or express how she feels about either guy . When Mindy ropes Caleb into taking her on a trail ride, she insists on riding an ailing Pegasus, ignoring Amy's warning that the horse should not be used . This results in a calculated photo - op for Mindy with paparazzi tipped off by her agent . The photographers get too close and spook Pegasus, dropping Mindy off his back, but causing stone bruises and a chipped bone for Pegasus . Lou eventually kicks Mindy out for behaving as a spoiled rich girl and disrupting the peace at Heartland, and she drives off into the sunset . She does leave Amy a parting gift, in the form of a very flashy, one of a kind belt, which was for sale at Maggie's for $995 . Amy promptly gives this to Soraya, with whom she was fighting over Amy's not sharing that Mindy was taking riding lessons at Heartland . </Td> </Tr> <Tr> <Th> 25 </Th> <Td> 12 </Td> <Td> "Divorce Horse" </Td> <Td> Dean Bennett </Td> <Td> Heather Conkie </Td> <Td> January 18, 2009 (2009 - 01 - 18) </Td> <Td> 212 </Td> </Tr> <Tr> <Td_colspan="7"> Mackenzie Hutton returns to Heartland with a fiancé, Ian, who she met after dumping her real estate agent boyfriend in New York . Mackenzie has changed quite a bit from her last visit to Heartland . She has given up the pretense of allergies to gluten, dairy, sugar, food that is not certified organic, and caffeine . She is also much more relaxed and happy with her easygoing husband - to - be in the picture . She has also taken a page from Lou's book and quit her job to be her own boss, running a little art gallery in the Village . When Mackenzie arrives at Heartland, she is talking about a small wedding (under 50 guests) held outside near the dude ranch, with a BBQ cookout reception . Lisa (with the best of intentions) meddles with Lou's plans for Mackenzie, since she knows the Huttons and their high - society lifestyle . Lisa and Mackenzie's mom convince her that she would be happier with a sit - down reception dinner and a tent and roses and peonies for table settings, rather than what she and Ian had been hoping for . Lisa also meddles in Lou's personal life, giving her email to a friend, who passed it on to another friend's single son . Peter, the young man, emails Lou, but she has to decide if she wants to respond . In the meantime, Amy has been treating another horse for Lisa, an Andalusian beauty named Diva . Lisa claims the horse is cursed, calling her "Diva girl, the divorce horse", as everyone who has owned the horse has become divorced . She is moody and temperamental, and Lisa asks Amy to figure her out, since Diva has been returned three times after being rehomed . With Ty and Caleb's help, Amy determines that Diva just needs to be a horse, and hates to be kept in a stall . Unfortunately, this means that Lisa cannot sell her as a show horse . She ultimately decides to give Diva to Mackenzie, who had taken a real shine to her, and would be able to keep her at her inlaws' ranch in Montana . While Mackenzie and Ian had been fighting during the episode over whether to even get married after their plans were hijacked, they resolve their differences and remember how much they love one another . The episode ends with Mackenzie and Ian saying their vows in the company of the Heartland family, at sunset in front of the dude ranch cabins and overlooking the pond . </Td> </Tr>

When do amy and ty get back together in season 4