Help! Plant newb here 👋🏻 I’ve had this cactus for about 2.5 years. After a year I finally figured out how to properly water cactuses and he was doing so well that he needed a bigger pot (there was originally 2 but then he grew 2 babies)… well that’s when the issues started. Mistakes were made in this process and I caused root rot with improper soil/drainage. (This was done in the fall) After figuring this out and losing one of the babies 😭… I cleaned up the rot, repotted him in proper soil etc.. (I did this 15 days ago) he seemed to be doing much better again. Had regained some colour. Well… now I’ve noticed the smallest one has a huge black spot on the back.. anyone know what to do?… is this a sign that he’s healing from the rot…? Or that I didn’t do well enough cleaning it off and he’s still rotting?? I misted the soil a few days after cleaning him up but otherwise have not watered him at all since. (The new soil was dry) *last photo is from the day I cleaned him up