Max Martin's daughter basically persuaded him to work with Ariana Grande and help create her quite popular single 'Problem'.
In an interesting look at the song's creation by Rolling Stone, your friend and ours Wendy Goldstein, who is of course Grande’s A&R rep at Republic, revealed that she spent two years trying to get Martin involved.
"He has a young daughter that’s a huge Ariana fan," Goldstein explained. "He said, ‘I’ve never seen my daughter excited about someone that I’ve worked with, and that’s really saying something.’"
He's also worked on a handful of other songs for the album, which is quite exciting really.