United Kingdom, Dec. 2 -- Adam Sandler finds it harder to make his daughters laugh now that they are older.

The Happy Gilmore star has Sadie, 19, and Sunny, 17, with his wife Jackie but admits that it is something of a challenge to get laughs from the teenagers.

Speaking to David Letterman on My Next Guest Needs No Introduction, Adam said: "They used to laugh easier. Now they're older and they judge you a little bit. I do hear, 'Oh, don't say this.'"

However, getting his children to laugh is still the "greatest thing" that Sandler can hope for.

He said: "You're happiest when they're happy."

Sandler stars alongside George Clooney in the new movie Jay Kelly and recalled the special way the Hollywood icon made sure he and his family fel...