Lennon and Maisy from ABC's hit show Nashville have filmed a video for an original song to accompany the release of their first children's book.

15-year-old Lennon and 11-year-old Maisy Stella portray Maddie and Daphne Conrad, the daughters of country star Rayna James, on the show, and they also perform together in real life. But the talented sisters took a creative detour for their new project, a children's picture book titled In the Waves.

The book tells the story of two girls on an imaginary adventure that begins in their bathtub and ends up at the seashore, where they build sandcastles, surf and even swim with whales. The story unfolds to the lyrics of an original song the girls wrote seven years ago.

"We were in this big Jacuzzi at our aunt and uncle's house," Lennon tells People magazine. "We wrote this chorus, well, we didn't even write it — we sort of just started singing it!"

That eventually developed into the idea for a book accompanied by an original song.

"To be honest, I tried to step out of my comfort zone," says Lennon, who's more at home with rootsy, folk-based material. "And Maisy is into pop, but this song is for kids."

The girls' mother painted the backdrop for the video, which features the sisters in a fun performance. Lennon had to fight her way through the shoot, which took place when she was in the middle of a bout with the flu. Check out the results above, and visit Amazon for more information about the book.