For all of social media’s benefits, it also has its downsides, one of which is that it makes life easier for obsessive fans. One superfan, known as “Stalker Sarah,” has practically made a career of it despite her young age, getting thousands of pics of famous stars. However, it was a given that she would eventually upset at least one of them, and now it’s happened as she’s ticked off Demi Lovato, whose Instagram has made her opinion of the young girl very clear.

If you’re not familiar with her, Sarah M., better known as “Stalker Sarah,” she is a celebrity megafan who has uploaded thousands of selfies of herself with celebrities over the years; as of 2013, she’d already posted over 6,000. In an article about her in The New York Times, it was noted that she has an eye for which up-and-coming talents are going to become breakout stars and is relied on by the paparazzi for her ability to amass info and track celebs just as well, if not better, than they do.

The controversy with Demi Lovato stems from one of Sarah’s more recent photos, taken with Lovato’s half-sister, Madison De La Garza, a child actress and celebrity in her own right. Sharing the photo on Instagram, Sarah captioned it, “Crave with my babe @maddieleedelagarza.” But this didn’t sit well with the “Heart Attack” singer, who responded, “THIS IS MY 14 YEAR OLD BABY SISTER. You are a 20 year old fame LEECH. SHE IS NOT YOUR BABE. [sic]”

However, “Stalker Sarah” apparently took it in stride, countering by posting another image: this time, of texts we’re to believe are from Madison De La Garza, apologizing for the drama caused by the photo of the two of them together. As of this writing, neither De La Garza nor Lovato has commented on this post and whether it’s legit.

And if you think Madison De La Garza’s sister is overreacting, keep in mind that not only was Sarah also Demi Lovato’s stalker once, but Lovato warned her about getting too close. Last month, Sarah posted a photo of herself with Lovato that read, “Having a blast at @dallaslovatome’s showcase with my girl @ddlovato ❤️ @maddieleedelagarza just killed it on stage! So proud of my babes. [sic]” In response, Lovato angrily posted in the comments saying, “I’m not your f***ing girl. If I was you would not be asking for pictures [sic],” implying that stalking and a photo do not make people friends, and that Sarah should “Stay the f*** away from [Lovato] and most importantly [her] family. [sic]”