06/06/2007 at 03:10 PM EDT
famously gets along with ex-wife Demi Moore'
s new husband, Ashton Kutcher
– but, he reveals, it wasn't always so easy.
The Live Free or Die Hard
star, 52, who has said he even vacations with his ex
and Kutcher, tells the July issue of Playboy
that it was pal Will Smith
who helped him get over his jealousy when Moore and Kutcher first started dating.
"During some very dark hours he talked to me about it," Willis says. "He said, 'Dude, you've got to do whatever it takes to get the kids and all the spouses or the girlfriend together. You've got to show your kids it's okay.' It was like a light went on. Ding.
So Will, thanks. And thanks for all those good movies you're making."
(The New York Post's Page Six
column was first to report those comments.)
Of course, now he and Kutcher, 29, are pals. "In the luck of the draw I am fortunate to have Ashton in the family," Willis says. "It took a long time for people to wrap their minds around the fact that I could be friends with my ex-wife's new husband, but we are friends."
Willis, whose 18-year-old daughter Rumer is friends with Lindsay Lohan
, says both he and Moore have talked to children about drugs: "We have an ongoing conversation. They have the gene, and we warn them: 'You have a predisposition to be an alcoholic.' It's on her side of the family and mine. It's something to be aware of. My kids are strongly antidrug."
Plus, Willis says he makes sure to spend lots of quality time with his daughters (he and Moore are also parents to Scout, 15, and Tallulah, 13). "When you have kids, it is so much more fun," he said Wednesday on Ryan Seacrest's KIIS-FM radio show. "My three daughters are my three favorite people on earth."
The secret to his great relationship with Moore? "A lot of people have a hard time letting go of the things that can end a relationship, but we've managed to put the kids first," he told Seacrest. "Here's the trick: Try not to take your time on earth for granted. ... Death waits for us all. The only answer is to get out there and live each day."