It’s a semi popular head-cannon on Tumblr and Twitters that Butters Stotch has D.I.D or OSDD.
Based on his various personas and Victor Chaos in the Post Covid special.
Butters was diagnosed with D.I.D by Doctor Janus but Doctor Janus was a insane man who himself had a split personality and all Butter’s did was play pretend characters that his family thought where multiple personalities because they are stupid.
I can see it the abuse he experienced could lead to DID.
In City Sushi it was shown that Butters was just playing like kids do. The adults misinterpreted it to be DID because of insane Dr. Janus that actually had the DID. The Post Covid specials were an alternate reality so I do not think any of that counts.