Millie Bobby Brown arrives at Netflix's "Stranger Things 3" world premiere. File photo/TNS

Four years ago, hotel heiress and celebrity socialite Paris Hilton called gay men disgusting, for which she was panned by the media and public alike. That she apologised later for her comment is another thing, but clearly she has not learnt from her mistakes.

Now she shot off her mouth again, this time her target being teen star Millie Bobby Brown. Hilton called Brown, who is barely 15, "hot,"

This infuriated actress Evan Rachel Wood, who is very protective about Millie Bobby Brown. Even Demogorgons or Godzilla are lesser threats than Paris Hilton.

A short spat between the “Westworld” actress Wood and the hotel heiress broke out on Instagram Tuesday after the “Stranger Things” star posted photos of herself in a pink, cheetah-print dress. Hilton praised Brown’s appearance in the comments, but Wood was quick to point out the actress’ young age.

“That’s hot,” Hilton commented on the post, prompting Wood to reply, “She’s 15.”

Their curt exchange sparked debate among other commenters about what should be considered age-appropriate on social media. Some sided with Hilton, arguing that the socialite and DJ has all but trademarked the phrase “that’s hot,” since she came to fame and likely didn’t mean anything by it. Others agreed with Wood, reemphasising Brown’s status as a minor and shaming Hilton for her crass choice of words.

“I just find it disgusting that a grown woman finds it okay to call a 15-year-old hot, catchphrase or not,” one person wrote. “All power to Millie for wearing a cute dress and not caring what others think, but grown adults should not be calling children ‘hot.’ Beautiful is a much better word for an adult to call a young lady.”

A third category of commenters ignored the older celebrities completely, instead blaming Brown for dressing herself and sharing the snap. The “Godzilla: King of the Monsters” actress has a history of being attacked by cyberbullies and last year left Twitter because of similarly judgmental and cruel treatment online.

The child star has since been an outspoken anti-bullying advocate and encourages others to be kind on social media. That clearly hasn’t stopped some from continuing to ridicule the teen from behind their screens.

Wood, once a child star herself, who has been open about being sexualized in her youth, often uses social media to call attention to social issues important to her — especially when it comes to respecting women of all ages. Brown is also known for her strong social media presence but has yet to weigh in on the exchange between Wood and Hilton.