Camila Alves Reveals Son Livingston, 5½, Was a 'Nightmare from Day One' — But He's 'Sweet' Now

Camila Alves and Matthew McConaughey have three beautiful kids but parenting them hasn't always been easy.

In PEOPLE's exclusive sneak peek of new YouTube series, Mom2Mom, Alves reflects on raising her youngest child, son Livingston, who turns 6 on Dec. 28. "It was different with all my kids. My two oldest were so good. And my third came along and he was a nightmare from day one," the mother of three recalls to host Carissa Culiner.

"He was really, really attached to me. He would just throw fits and cry. He would not get out of that stage until he was like 4," Alves says. "He was horrible. I shouldn't say horrible, he wasn't horrible but the situation was horrible."

Alves, 36, and McConaughey, 49, are also parents to 8-year-old daughter Vida, 8, and 10-year-old son Levi.

"I was like, 'This was so hard. [Livingston]'s such a troublemaker.' Now that he's in a sweet stage, he came out of the dark side. I was so deep into this, like craziness," Alves adds.

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As for the ups and downs of parenting multiple kids, Alves has some stories she can share. "I don't know if I'm an expert, but let's just say I have some experience," she says.

And the star shares that both she and her Oscar-winning husband switch off being the disciplinarian.

"We both are. I can be a little bit more strict with being worried about things and what can go wrong," Alves says. "He's [a worrywart] with other stuff but not with the kids. I never used to be like that but being a mom definitely got me more strict and a little bit more worried. I'm working on that."

McConaughey previously revealed that he and Alves take a blended approach to parenting. "We mix the 'Alright, alright, alright' into the discipline," the actor joked on the Today show in September. "The main thing is that my wife and I, Camila, we have a similar moral bottom line. And as you learn, if you have kids, every day they get older, you realize how much more it's really DNA."

The father of three added, "We can nudge 'em and shepherd 'em, et cetera et cetera, but they are who they are. And right now, I'm just happy to say we have three healthy ones and they're very much individuals."

In Mom2Mom, Culiner chats with celebrity moms about their parenting adventures, covering everything from meltdowns to milestones. "Mom2Mom is the ultimate 'safe zone,' where moms can share stories and feel supported. Because, let's face it, motherhood is full of unexpected moments, and sometimes you just need a drink, a laugh, and a girlfriend who's been there," the show description reads.

Mom2Mom airs on E! News' YouTube channel.