Oh, baby, baby. Ashton Kutcher revealed that he is a bit concerned about the impending birth of his second child with pregnant wife Mila Kunis during a Wednesday, October 5, appearance on The Tonight Show Starring Jimmy Fallon.

After Jimmy Fallon congratulated Kutcher, 38, on becoming a second-time dad — he and Kunis, 33, welcomed daughter Wyatt in October 2014 — the actor joked about being unprepared.

“I’m worried. The first one, I was almost like a doula. I was reading every book. I was ready. I had a catcher’s mitt on. This one, I haven’t done anything,” the Ranch star admitted. “I’m like, ‘Well, we already didn’t break the first one.’ They’re really durable. They don’t break very easily. You have to really try to break them.”

Also durable? The toys that Kutcher and Kunis — who quietly tied the knot on July 4th weekend in 2015 after three years together — have been spoiling their firstborn with. According to the That ‘70s Show alum, an “entire toolbox” is needed just to disassemble one.

“They make everything too safe now,” he complained to Fallon, 42. “When I was a kid, we were riding in the back of a pickup truck on the wheel well, just trying not to fall out.”

As the actor made an attempt to demonstrate what his childhood car rides looked like, he accidentally suffered a wardrobe malfunction. “I just ripped the crotch out of my pants,” he admitted. “I think I had, like, a nut hanging out.”

To hear more of Kutcher’s hilarious parenting tales, watch the clip above.

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