Nicole Richie reveals daughter Harlow, 18, goes by new name

Nicole Richie’s daughter is going by a different first name.

Richie — who shares 18-year-old Harlow Winter Kate Richie Madden with her husband, Joel Madden — revealed that her eldest child actually uses the moniker Kate.

“She goes by her middle name. She has her whole life,” Nicole explained to People after her recent birthday post in honor of her daughter sparked confusion.

“I didn’t look [at the comments], but it makes sense,” she acknowledged of the online reactions.

Earlier this week, the reality star-turned-fashion designer, 44, shared an Instagram carousel featuring photos of her daughter through the years.

“18 years of you ♥️🎂,” she captioned the upload, going on to tag @katemaddennn.

“How to make a grown man cry!!! 😭😭😭😭😭😭😭❤️❤️❤️❤️❤️,” Joel, 46, gushed beneath the snaps. “Love you Kate! You’re a bad ass [sic]! Never forget it! Happy 18!! 🎉🎉❤️❤️🎉.”

Many fans couldn’t believe that Nicole and the Good Charlotte frontman’s firstborn was already a legal adult, while others remarked how the teen looks just like her mom.

A handful also praised the couple for doing “such a good job keeping her out of the public eye.”

However, plenty of observers noticed the username, writing things like, “Happy Birthday!? Did she change her name?”

Kate — who was born with blond, curly hair — now sports long, dark locks. Her public Instagram page contains pictures of her relaxing on the beach, partying at nightclubs, going out to eat and enjoying vacations.

Nicole and Joel, who wed in December 2010, are also parents to 16-year-old son Sparrow James Midnight Madden.