<P> In the second season episode "Sexy", Blaine reveals he has a strained relationship with his father . </P> <P> As Blaine, Criss features in many musical performances, which have been released as singles, available for download . His first performance, "Teenage Dream" by Katy Perry, was featured on the soundtrack album Glee: The Music, Volume 4 . It reached number eight on the Billboard Hot 100 in the week ending November 27, 2010, and was the best - selling song in the U.S. that week, selling 214,000 copies: the largest figure for a Glee title . It was only the second U.S. - certified gold single in the show's history . Both Billboard's Jillian Mapes and Erica Futterman of Rolling Stone deemed "Teenage Dream" the best song of "Never Been Kissed", the episode in which it featured . The Daily News's Anthony Benigno gave the song an "A", and noted that it was "flawless" and improved on Perry's original . The performance was nominated for the Best Gay Moment of the Year and Favorite Music Video awards at the 2010 AfterElton.com Visibility Awards . A Billboard cover - feature on Criss noted that the performance "arguably ushered in the trend of more current pop hits being reworked by the (Glee) cast ." </P> <P> Later songs performed by Blaine and the Warblers became popular enough to warrant a Warbler soundtrack album, Glee: The Music Presents the Warblers . The tracks had sold over 1.3 million copies as singles by the time the album was released . Blaine performed the lead vocal on covers of Train's "Hey, Soul Sister", which peaked at number 32 in Canada, "Bills, Bills, Bills" by Destiny's Child, which reached number 44 in the U.S., and Robin Thicke's "When I Get You Alone", which got to number 47 on the Billboard Hot 100 . Criss downplayed his performance of "Bills, Bills, Bills", and jested that he ought to issue the group's lead singer, Beyoncé Knowles, an apology for his cover . Blaine also led on "Silly Love Songs" by Wings, and Maroon 5's "Misery", which reached 45 and 52 respectively in the U.S., and Pink's "Raise Your Glass", which peaked at number 30 in Australia . </P> <P> Blaine duetted with Kurt on Frank Loesser's "Baby, It's Cold Outside", which was included on Glee: The Music, The Christmas Album and reached number 53 in Canada . It was reportedly the most downloaded track of the album, and called "by far the gayest thing that has ever been on TV" by Colfer . Murphy expressed his pride in the number for "push (ing) the envelope a bit ." Jessica Ronayne of Zap2it called the duet one of the Christmas episode's few saving graces . Blaine and Kurt also duetted on Neon Trees' "Animal" and Hey Monday's "Candles", which peaked at 62 and 71 in the U.S. respectively . In an April 2011 interview, Criss stated that he did not feel established enough within the cast to make song suggestions, but had mentioned liking "Animal" to Murphy, who included it in a script soon thereafter . Blaine shared a duet of "Don't You Want Me" by The Human League with Rachel, which Reiter deemed a musical highlight of the episode "Blame It on the Alcohol". It was included on Glee: The Music, Volume 5, and peaked at number 44 in Australia . </P>

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