Is it normal to sleep nonstop for three weeks straight

So there is this guy who moved in. Its my roommates younger brother or age 15. This person will never stop sleeping, though. I think it would be fair to declare them legally dead at this point. They won't even get up to eat and they have been doing this since Christmas break. Its kind of annoying since I tend to cook for the house and ill ask them an hour ahead of time "Are you going to eat dinner" and they say "Yes".

However, I check an hour later and they are dead. I kind of feel like kicking them for being such a fucking lazy piece of shit. Why would anyone sleep this much, and how do you get them to stop? Generally, they would stay up at least while playing games but now its just dead sleep for over 3 weeks.

I don't see how this is normal, healthy, or helpful in any manner. They won't even do chores anymore and I end up doing them for this person since they will not wake up. I know this is a Pokemon reference but if there was ever a human version of a Snorlax, its this person. Seriously all they DO IS SLEEP! Like I am wondering if maybe they are going to go into a coma or something. I'm not exaggerating either. They will sleeping for maybe 20 hours straight and its not like they do anything extensive.