Help me remember the name

I saved this to read later, but I lost the name. I think it is a BL story, but I read the summary only. It’s about a guy who gets sick I think. His family member (I think?) goes to the mountain or something to get an omen for help or something? If the omen shows an old person, it’s a big problem. If it’s a young person, it’s a small problem. Something like that?? Sorry I can’t remember the summary I read very clearly.