Lisa Kudrow's son used to call Jennifer Aniston "Mummy".
The 57-year-old actress was often accompanied to work on the set of Friends by her only child Julian, now 23, and though she loved the bond he developed with her castmate, she admitted it led to some confusion from the youngster.
Speaking to Conan O'Brien, Kudrow said: "He got a little confused. I know that he really was obsessed with Jen."
Kudrow — who was pregnant during the fourth season of the show — added, "He'd fly into her lap. 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."
"But then at home, she'd be on TV, and he'd go, 'Mummy!'"
Kudrow, who is married to businessman Michel Stern, revealed Julian has seen episodes of the show in recent years so he could talk to his friends about it, and she joked he was more impressed by everyone else's performances than her own portrayal of Phoebe Buffay.
She said: "I know he hasn't seen every episode. I know for a while, in school, people were watching it. And he kind of felt like he had to, so that he can participate in what everyone else was watching. And he did really think that everybody else was very funny on the show."
Aniston was among the stars to wish Julian a Happy Birthday when her friend and former co-star shared some photos of him on Instagram to mark the occasion earlier this month.
The Morning Show star commented on the May 7 post: "Happy Birthday, Juls!!! Feels like yesterday that you arrived.(sic)"
Kudrow recently admitted she'd got "more sensitive" when she had her son and stopped finding things as funny as she used to.
She said: “When I became a mother, everything changed. The instant my son arrived, I thought, 'Oh, okay, now I get it. Nothing else is ever going to be as important as this.'
“And my outlook on life changed too — one thing that's kind of sad is that a lot of things that I had found funny before just stopped being funny to me then, and there were a lot of things on TV and in the movies that I couldn't watch anymore.
"Any sort of doctor shows with kids ending up in the emergency room, anything that involved children getting hurt. Before, I'd been able to see movies such as Sophie's Choice and Schindler's List — I couldn't even begin to watch them now. I guess I got sensitive!"
Watch Kudrow's interview on Conan here:
— BANG SHOWBIZ
Photos: TPG News/Click Photos