A student in Dundee, Scotland has been frightened to discover that a mystery doppelganger has spent two years recreating her social media posts, according to her sister.
In a Facebook post Linzi Cowan said the lookalike has re-enacted the poses, outfits, and even captions posted by her sister Chloe Cowan on Instagram.
She said the mystery user has even acted out by video, scenes from photographs of Chloe and her father, who has since passed away, according to the Daily Mail.
The post was shared 11,000 times before being deleted this afternoon.
Police Scotland told MailOnline they could not confirm whether the incident had been reported to them either in Dundee or elsewhere.
It is unclear who the Instagram user is or what her motivation may be.
Chloe's sister Linzi posted about the strange online behaviour by Chloe's supposed doppelganger saying she wanted to warn people of the "dangers of social media".
Her Facebook post read: "Don't even know where to start with this but just want to let people know the dangers of social media.
"My sister Chloe is at Dundee university and another girl living in Dundee (who my sister wasn't aware of until this week) has been reenacting her life on instagram for almost 2 years.
"This girls stalking behaviour is to the extreme of reenacting videos of a photo album that Chloe posted of my dad who past away (gives me the shivers when I think about it).
"This girl doesn't follow my sister on social media and had made a fake account to stalk her without her knowing.
"Her behaviour is not ok and I just wanted this out in the open for people to be aware of just how scary social media can be.
"My sister should not have to hide away in worry of her every move being stalked by another girl! Imitation is flattering but this is just too far!"
Linzi shared a series of photos comparing the original Instagram posts by Chloe with those by the copycat.
In one, Chloe is posing in a little black dress, sporting Mickey Mouse ears and holding a cane.
In the replica her lookalike not only copies the ears and cane and wears a similar dress, she also poses in the same left-foot-forward pose and even used the same caption: "social life wua can't see you", including the "poo" emoji used by Chloe in the original.
Another picture from Chloe shows her wearing black jeans and open-toed shoes, with a cropped black top.
She is leaning to her right with her elbow out and her right hand up to the side of her head. The copycat replicates the outfit and the pose with eerie accuracy - adding an almost-identical caption.
Linzi's Facebook post was shared more than 11,000 times after she posted it yesterday, but was deleted at around 3.30pm today after coming to national media attention.
The copycat Instagram account, "honeybasra18xo", has also been deleted.
Police Scotland in Dundee told MailOnline they had no record of any crime having been reported but believed the woman was resident in Glasgow.
Police in Glasgow could not confirm whether this incident had been reported to them.