Happy birthday, Ashton Kutcher! The Ranch star turns 40 years old today, and if we've learned anything about him through the years, it's that he's likely spending the big day in his favorite place: at home with his wife and kids.

The actor married his former That '70s Show co-star Mila Kunis back in 2015, and they have two kids together: 3-year-old Wyatt Isabelle and 1-year-old Dimitri Portwood. While the proud dad doesn't like to share photos of his kids, he definitely doesn't have a problem gushing over them.

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We've rounded up every time Kutcher had the sweetest things to say about Kunis and their little clan.

1. "You think you know how much you can love another person, and then you have a child and realize you didn't know. It's infinitely rewarding." –on The Ellen DeGeneres Show

2. "Staying home the first couple of weeks, I've learned the little things that will calm down the baby, so I feel like I'm the baby whisperer now." –on Conan

3. "She's the greatest mom. I go to work every day, and I come home and she's perfect. And it just seems like everything went amazing. And I know that something probably didn't go amazing, but she never tells … it's unbelievable. She's incredible." –on The Ellen DeGeneres Show

4. On keeping Wyatt away from the spotlight: "When it is a choice that she is making, then I think it is fine. As long as it's not a choice that she is making, it is my job to protect her from all this nonsense." –on Entertainment Tonight

5. "The first one I almost became a doula. I read every book. I had a catcher's mitt on. This one I didn't do anything. I'm like, 'Well, we already didn't break the first one!' They're really durable." –on The Tonight Show Starring Jimmy Fallon

6. "We just want to know our kid. We want to be the people that know what to do when the baby's crying to make the baby not cry anymore. We want to know, like, when she makes a little face or something, we want to be emotionally in touch with her. And I think the only way to do that is by being the one who's there." –on The Ellen DeGeneres Show

7. On reporters asking Kunis what she's wearing: "I prize her as the most valuable person in the world to me. You have a chance to sit with Mila Kunis and that's what you ask her?" –at the Tech My Way conference

8. "When my wife and I had these kids and we got to share that amazing, amazing, amazing honor, my first response was, I wanted to call my parents and say, 'I'm sorry, because I never knew how much you loved me.'" –accepting the Robert D. Ray Pillar of Character award.