As the conversation turned to parenting, Paltrow admitted that she "came into it on tenterhooks" when it came to acting as a stepparent to Falchuk's teenage daughter Isabella and son Brody after she and Falchuk tied the knot in 2018.
"It's funny because there's just no playbook for how to do it and nobody says, 'Hey, you're going to be a stepmother,' " Paltrow said about learning how to stepparent. "I don't know, I think there's like this archetypal evil stepmother and this inference that it's going to be this fraught thing, so I think I came into it on tenterhooks, like, 'Oh my Gosh.' "
"It's like you can only kind of do the wrong thing, especially because your kids were more resistant," she added.
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Falchuk, on his part, admitted that his children were indeed hesitant about ditching their "great little pack" when he and Paltrow married. He added that he and his wife have both noted throughout their marriage, however, that her own "hesitancy" about the situation "probably freaked them out, too."
"That's my only regret," Paltrow said about the adjustment to living as a stepparent. "Is that whenever it was, however many years ago, when I was just like, 'F--- it, these are my kids, I love them. I'm not going to be scared to discipline them or draw the boundary.' That's really what shifted everything, I feel like."
Paltrow also offered up advice for anyone who may ask about being a stepparent, saying, "From day one, just like really treat them as your kid."
"Don't have trepidation because they're not [yours] and you don't have jurisdiction and God forbid — be your full self as a parent with all the love and all the acceptance and all the boundaries," she continued. "I just wish I had done that earlier."
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Falchuk later called Paltrow "a spectacular stepmom" during the podcast, noting that his children have a relationship with her entirely "outside of me."
"You're a spectacular stepmom, like thank goodness for you," he said. "You know you are. My kids absolutely — I mean, you have a relationship with them outside of me."
"They talk to you all the time, they come to you for advice all the time, they rely on you," Falchuk added.
"I have two beautiful stepchildren, who are the same age as mine," Paltrow — who shares daughter Apple, 18, and son Moses, 16, with ex Chris Martin — began. "It's funny because when I became a stepmother, when I knew I was going to become a stepmother, I was like, 'S—, I have no idea how to do this. There's nothing to read. What do I do? Where do I step in? Where do I not? Like, how do I do this?' "
"It's been a really interesting challenge for me and I love them," she added. "I've learned so much about myself through the process."