The 'Tonight Show' host - who has daughters Winnie and Franny with his wife Nancy Juvonen - announced he has a "massive" project in the works with the 'Hustlers' actress and joked that she agreed to write a story together after the 'On the Floor' hitmaker scrapped his idea for a duet together.
Fallon told 'Entertainment Tonight': "The next idea we have… it involves JLo and it's massive. We always wanted to do something together and of course I was like, 'We should do a song together.' She was like, 'No, I can't. I'm busy. Oh, next time.'" About Jennifer, who has Max and Emme with her ex-husband Marc Anthony, Fallon added, "We both have kids. She's an amazing mom, let's think of something fun, a good children's book where we can get together and do something." Jimmy also joked that the book will "help teach babies Spanish." He added, "It's really sweet. The artist is great. I think people will really like it. It's a lot of fun." While fans may have to wait for the collaboration, Jimmy has just released his new book 'Nana Loves You More' and is very "excited" about the story, which centers on his own relationship with his beloved grandparents.