SPOILER ALERT!!! You might not want to read this if you haven't seen Season 4 Episode 3, but it's really not much.
After the whole adventure with Eurus, John moved back in with Sherlock (as we all pretty much figured he would), and Sherlock is now helping him raise Rosie. She will grow up calling him Uncle Sherlock, but she will love him like another father, and Sherlock will love her just as much as John does.
Also, if Sherlock ever (somehow*) has a child of his own and the child's mother is out of the picture, then John will help him raise that child, and the two children will grow up not being biologically related, but calling each other cousins, and being as close as siblings.
(I actually had a dream once in which Sherlock had a daughter shortly after John did, and before the two girls were even fully grown, they were solving crimes, like their respective fathers before them. I've even considered turning that into a oneshot.)
*Also, I say somehow because I'm convinced that Sherlock is asexual (but not aromantic).
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Random Sherlock Headcanons
Fiksi PenggemarThese are just some random headcanons about BBC's Sherlock.
