How do I tell him he stinks??

My husbands uncle is staying with us. And for me honestly it’s dreadful, and I just want the 4 months to pass so he goes home. Anyways, his uncle does not like taking showers. He works with my husband from 8am to 6 pm sometimes longer, in construction. When my husband comes home he stinks but he goes in the shower right away and the smell of sweat and BO goes away. His uncle, on top of it, smokes, so he smells like BO And smoke, he showers every 3-4 days, IF that. Today I was going to eat dinner but his stench made me nauseous and I ended up going to our bedroom instead. I don’t want to hurt my husbands feelings, but I cant live like this either 😭... and I say my husbands cuz I was thinking of telling him “honey.. why don’t u tell your uncle to shower more often” or something.... so he tells his uncle. 🤢 any ideas?

UPDATE: told my husband and now he’s offended. Lol his truck got some water in it and we went out, I told him “it stinks in here” and he was like “why? Cuz of the humidity or cuz of my uncle??” 🙄 and his uncle is staying with us cuz my husband got him a job while he gets on his feet again. Gave him 4 months to b w us