"The first year with them was complicated," he says in an interview with USA Weekend. "They were crying a lot."
But as the toddlers approach their third birthday in October, it's a whole different ball game.
"The older they get, the more I love being a dad. Now that they're talking, I'm really loving the camp counselor end of parenting," he says. "I'm all about reasoning. If they fall and are okay but crying, David [Burtka, his partner] will be the hugger, and I'll be the 'Show me where it hurts; let's talk about it' one. I come from a family of lawyers, so explanation is crucial."
But the 40-year-old also loves playing with them!
"We do circus tricks together," says the Smurfs 2 and How I Met Your Mother star, who's president of a private magicians club in L.A. and has a "Magic Room" in his home.
And when he and his kids aren't hanging out in their backyard pool – "They're remarkable swimmers," he reveals – he's cherishing the more peaceful times. "I love reading books to them … I use different voices," says Neil, who his kids call "Poppa." "I like moments of quiet connection – like giving them back scratches."