Dax Shepard and Kristen Bell 'did not want a second child' at first. Here's why they changed their minds.

Dax Shepard is sharing details behind the decision to have a second child.

During an appearance on the Endless Honeymoon podcast, Shepard, 47, opened up about his two daughters — Lincoln, 9, and Delta, 7 — both of whom he shares with wife Kristen Bell.

“We did not want a second child,” he explained to a couple who called in for advice about growing their family. “It’s a bizarre conversation to start because [a family unit of three] is perfect, and it’s so much easier. You can take that little Subway sandwich anywhere, as I’m sure you guys are doing.”

The Parenthood alum explained that as Lincoln started growing, he and Bell realized it may be beneficial to have a second child so she can have a “playmate,” not just on their travels, but for the long haul of life.

“One is, we travel a lot. It’s not fair to bring this little human everywhere we go and deal only with adults. Like, we owe it to her to give her a playmate that travels with us everywhere,” he explained. “We love [Lincoln] enough to do something we don’t really wanna do, which is have a second, because we were so absolutely happy with just the one.”

Another reason for the decision, he later quipped, was to minimize the chances for Lincoln to become “spoiled” as an only child.

“Our kids already are so privileged beyond belief,” he said. “It rattles both of us being from very, you know, modest backgrounds. So, to make the spoiled bitch, my first born, live in the same room with another person [when she gets older] and have to share everything, like, I needed [Lincoln to learn] the force of compromise and sharing discomfort because I wasn’t going to give it to her any other way. So we just thought it would be really helpful to make her a better person, to have to deal with someone else.”

Another piece of advice Shepard gave was, should anyone decide to have a second child, to do it “as quick as possible.” His own daughters were born 20 months apart.

“Our kids are under two years apart, and for a minute that was difficult because you know, when you’re 5 and the baby is 3, that’s no fun,” he said. “I will say the corner we’ve turned is, like, now they party. Not only do they party together, they’re united against us, which I love."

He added, "If I’m giving it to one of the girls, the other one comes over, ‘You’re not being nice to Lincoln. You didn’t listen to what she said.' And I’m like, 'That’s right. That’s your role. You guys gang up and kill me. It’s you two against the world.' That stuff, I think, the lesser the age gap the easier it is to achieve."

Shepard and Bell have touched on their approaches to parenting in the past — including the fact that the entire family slept in same bed together for years.

"We just graduated from them sleeping on the floor on this trifold mattress," Bell told E! News in June. "So you can congratulate me — we did it, they now sleep in their room on beds right next to each other and they cuddle with each other instead of us."

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