The Ocean's Eleven star opened up about taking in a cocker spaniel mix named Einstein for a book titled My Old Dog: Rescued Pets With Remarkable Second Acts.

In the tome, George shares snaps of his beloved pooch, who was rescued from a shelter in 2010, aged five, just hours before he was due to be put down, and the actor reveals he has made a great pet.

"He was house-trained and had a great attitude. Age doesn't matter," he says. George also reveals Einstein now lives a glamorous life jetting all over the world with his famous owner, and spends a lot of time at the actor's villa in Italy.

"(He) has grown to love Italian food," George adds.

The star previously revealed he used a crafty trick to make sure the dog liked him at their first meeting.

"I start to panic that Einstein is not going to like me," he told Esquire magazine. "So I run into the kitchen, where I have these turkey meatballs, and I rub them all over my shoes... Who knew Einstein was such a food w**re on top of everything? He throws himself at my feet."

George and his wife Amal also have another cocker spaniel named Louie, and they recently added a basset hound mix named Millie to the family.

They rescued her from the San Gabriel Valley Humane Society shelter in California last week (ends01Nov15), and shelter bosses shared a sweet snap of the pair with their new pooch.

"It was a happy day at the shelter for Millie!" a statement from the shelter reads. "Millie was found without a home and hoping for food scraps outside of a local restaurant in San Gabriel earlier this month. Today her luck changed for the better when she was adopted by George and Amal Clooney... They were searching for a basset hound and saw Millie's picture on (adoption website) Petfinder. They did a 'meet and greet' with her ... and the happy, new family headed home together!... Congratulations to the Clooney family and thank you for adopting!"