Hey now, hey now, Hilary Duff 's husband has some thoughts about her comeback single "Mature."

While theories surrounding the inspiration behind the diss track has ranged from the singer's ex Joel Madden to Leonardo DiCaprio , who's garnered a reputation for dating women until they turn a certain age, Matthew Koma believes his wife was singing about someone significantly older.

"I think it could be about Bernie Sanders ," the musician quipped in a joint Apple Music 1 interview with Hilary on Dec. 4, saying that he feels "less threatened" by the 84-year-old than other possible muses fans have suggested. "I have a few of my own."

But, as Hilary joking pointed out, it would be "too obvious" to sing about Bernie and other men around his age, listing off examples in

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