George Clooney ''didn't think'' he would be a dad with twins at 56.

The 'Monuments Men' star absolutely adores his twins Ella and Alexander - who he shares with his wife Amal Clooney - but admits he would have never predicted his life would be like this.

Speaking from his home in Lake Como, Italy, ahead of the release of his new movie 'Suburbicon', he said: ''Suddenly, you're responsible for other people, which is terrifying. Amal's like an Olympic athlete. She's doing so beautifully.

''Right now my job is changing diapers and walking them around a little bit. I really didn't think at 56 that I would be the parent of twins. Don't make plans. You always have to just enjoy the ride.''

And George and Amal are said to be ''very hands-on parents''.

The source shared: ''They are very hands-on parents, but they also have some help. They also value their adult time and want to make sure that they are able to slip away for adult dinners and other things that they enjoy. With the help of their baby nurse, they are able to do that frequently.''

And the couple are ''happier than ever'' since becoming parents.

An insider said: ''Everything is going great with the babies. [George and Amal] are happier than they have ever been and really enjoying being parents ... They are truly in love and just want to be with the babies and not do much else.

''Amal's mother helps out a lot and can't get enough [of the babies]. If she doesn't see them for a few days, she is dying to come back. They have had a lot of friends visit and Amal's family is often around. There is always someone who can give a helping hand. That's given George and Amal an opportunity to be together and have some one-on-one time, too.''