Clearly you *haven't* read WP:NPA, otherwise you wouldn't have written this. It is difficult to understand why someone interested in Jeremy Sinden should instead rush across to his far less well-known brother's article and immediately feel the need to remove tags? The tags remain because the article is in severe need of a rewrite, not least because one of the main contributors has claimed to be a 'good friend' and a 'fan' of Marc Sinden from the age of 12(!), when they met on the set of the 'Hey Jude' video recording(!). Unfortunately this is the very same editor that was caught dragging along a bucket-load of socks to try and support various POV positions and outright puffery of Marc Sinden and Sinden-related articles. Amazingly enough, this editor and their socks have added Marc Sinden's name to around 130 articles on Wikipedia. 130! For someone who's less notable than my goldfish!
It's certainly true that the Jeremy Sinden article might lead one here, because of course there are no less than *three* mentions/links to Marcus' page from there - sadly there is not one single link from Marcus' back to Jeremy's, indeed his name has been expunged completely from the Marc Sinden article. It seems more than odd that you should seem so determined to enter an edit war in only your first day as an editor, instead of fixing the egregious error that would strike any true contemporary of Jeremy's immediately! May I therefore suggest you take three actions? 
1. Go read WP:NPA yet again, just in case it hasn't impinged. 
2. Add links and content to the Marc Sinden article that reflect and respect the memory of your school chum Jeremy Sinden, because in all the puffery of Marc, poor Jeremy seems to have been wholly ignored. 
3. Expand the content of the Jeremy Sinden article such that it *at least* matches the Marc Sinden article, because it is a disgrace that the puffed-up Marc Sinden article is perhaps ten times the size of the Jeremy Sinden article, when Jeremy was perhaps ten times more notable - go and put this right. 
Finally, as an observation; as a contemporary of Jeremy you would be around 60 years old - it is both surprising and disappointing that with such advanced age has not come the sense of insouciance, and the wisdom of seniors, that one might normally expect. May I suggest that you therefore refrain from further conflict and personal attacks, and put your editing efforts to work exclusively on the person you *do* know about? Thanks.