Lisa Kudrow Says Son Julian Thought Friends Costar Jennifer Aniston Was His Mom Growing Up

Gregg DeGuire/Getty Jennifer Aniston and Lisa Kudrow

The one with the mom mix up!

On Wednesday, Lisa Kudrow, 57, revealed on an episode of Conan that her son Julian, 23, used to think her Friends costar Jennifer Aniston was his mother.

The actress explained to host Conan O'Brien that her son spent so much time on the Friends set as a young child that he ended up getting confused as to who was his real mother.

"He got a little confused, I know that he was really obsessed with Jen Aniston," O'Brien began the conversation.

"He'd fly into her lap," Kudrow said of her son. "Well, she's a love bug, and that made sense. And I was always glad for anyone that Julian felt love for and felt from."

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"But then at home, she'd be on TV, and he'd go, 'Mommy!' " Kudrow shared with a laugh.

"I'm kind of analytical so I'm like, 'Is this wishful thinking? Do they have some kind of higher soul connection that I don't have with him?' " she said, teasing, "I'm happy for both of them."

Over the weekend, Kudrow paid tribute to her son on his birthday with a sweet social media post.

"FaceTime with my boy to say HAPPY BIRTHDAY!!" the Emmy winner captioned a series of screenshots on Instagram.

RELATED VIDEO: Lisa Kudrow Reveals the Sweet Way Her Friends Co-Stars Embraced Her Pregnancy

Kudrow was pregnant with Julian while filming season 4 of Friends, and her pregnancy was written into the show. "The six of us would do a huddle backstage and just say, 'All right, have a good show, love you love you love you love you,' " she recalled of the experience to PEOPLE in 2018.

"And when I was pregnant, then they would say, 'Have a great show, love you love you — love you, little Julian!' " the mom of one previously raved. "Cause we knew it was a boy and that was his name. So sweet, they included my little fetus in the huddle."

Kudrow and her fellow Friends cast members recently filmed the long-awaited reunion special, which was delayed several times due to the COVID pandemic and was supposed to premiere in May 2020.

"It's not a reboot," she shared back in January. "It's not like a scripted thing, we're not portraying our characters. It's us getting together, which just doesn't happen a lot and has never happened in front of other people since 2004 when we stopped ... I think it'll be great."