John Lithgow has released his eighth children’s book, this one about two mischievous dogs named Fanny and Blue.

“I Got Two Dogs” was a “lot of fun to write,” Lithgow told “The Early Show.” The book’s rhyming text is the lyrics to a sing-along song that’s included on a CD that comes with the book. “Out of all the songs that I’ve made up for kids, this is their absolute favorite,” he says.

“I Got Two Dogs” was illustrated by Robert Newbecker. “One of the nice things about these books is I’ve worked with five or six different illustrators, and they just all are superb.”

Lithgow released his first children’s music CD almost 10 years ago, but has been entertaining pint-sized audiences for decades. “It’s been very organic,” Lithgow says. “It all started with my own little children, and all of their friends, and my oldest is 36 now, so it’s a long, long time,” said the grandfather of two.

Lithgow is also starring in a hit play on Broadway, “All My Sons,” with Dianne Wiest, Patrick Wilson and Katie Holmes. The Emmy- and Tony Award-winning actor says his career couldn’t be more exciting – or varied. “I’m practically schizophrenic these days,” Lithgow says.