Things have gotten way too personal for TikTok's most-followed personality, and after getting an online threat ... her family's hired round-the-clock security.
Law enforcement sources tell TMZ ... Charli D'Amelio got a scare on July 8 when someone posted on social media, claiming they were going to show up at her house.
No one followed through on that threat, apparently, but we're told cops are investigating. The situation alarmed Charli and her fam enough to hire cops to keep an eye on things.
Our sources say the family is paying the OT to have police officers surveil their property for the foreseeable future, because this isn't the first frightening incident they've experienced.
We're told Charli's also been the victim of multiple "swatting" calls, where random people have falsely reported an emergency at her home ... then authorities show up to nothing.
Charli is a dancer who has quickly become a sensation on the social media platform. Since first posting her dance videos in the summer of 2019, she's amassed nearly 75 MILLION followers ... making her the most popular TikTok account.