Billie Eilish fans are completely shocked to learn that she has a famous mother

In the Hollywood industry, it is not uncommon for entire families to be in the spotlight.

From the Beckhams and the Kardashians to Susan Sarandon and her daughter or Catherine Zeta-Jones and her daughter, it’s clear that the saying “the apple doesn’t fall far from the tree” applies to many celebrities, including Billie Eilish.

Fans of the 22-year-old “Ocean Eyes” singer were completely shocked to find out that she has a famous mother who once made a cameo appearance on a major ’90s show.

(Todd Williamson/NBC / Contributor / Getty Images)

Billie’s mother, Maggie Baird, starred in perhaps the most popular sitcom of all time in 1999.

The result of FriendsIn “The One Where Joey Loses His Audience,” Maggie plays Casting Director 2 while Joey Tribbiani (Matt LeBlanc) auditions for her.

The scene shows Joey losing a role he actually needed to pay for his medical care due to a painful hernia.

Unable to lift the product because of the pain, he suggests instead, “Or I could just point? Blah, blah, blah, Purina One. Point to a bag today.”

Maggie Baird appears in a scene from Friends. (Warner Bros)

The clip has since resurfaced on social media, and many fans of both the TV show and the singer can hardly believe the unexpected crossover.

Many have since rushed to Instagram to share their reactions, with one writing: “HOW COULD I NEVER NOTICED THIS?”

“HOW COULD I NOT NOTICE,” echoed a second, while a third revealed: “I just watched this episode and now I’m annoyed that I didn’t notice.”

“I didn’t know that! How funny!!!” joked a fourth.

A fifth person chimed in: “OMG, NO WAY?!!!!!!!! WHAT? I’M GREAT!”

“WHEN I SAW HER ON THE SHOW I WAS SHOCKED,” admitted a sixth, while a seventh chimed in: “HOLY SHIT I THOUGHT SHE LOOKED FAMILIAR!”

“I didn’t know that and I’m on the final season,” tweeted one eighth, while another added: “Hooooly sh*t!!! That’s why I thought I knew her when I first saw the show! Wow!”

And one final Instagram user wondered: “So is Billie a Nepo baby?”

This is a entire a completely new conversation.

Fans were more than “shocked” that Billie’s mother made a brief appearance on Friends in the ’90s. (Instagram/@billieeilish)

Billie recently gave her fans a rare insight into her relationship with her ex-boyfriend Jesse Rutherford (33), amid allegations of infidelity.

Speaking to Rolling Stone, the “Lunch” hitmaker confirmed that she and the frontman of “The Neighbourhood” continue to have a good relationship.

“This is my guy, truly one of my favorite people in the world,” she said.

Regarding her current relationship status, Billie added: “I never plan on going out again. That’s obviously not true.”

“But no, I can’t imagine getting into a serious relationship with anyone until I find someone I’m really comfortable with, and that’s not what I’m interested in right now.”