I had three sons and even with daily showers mys boy could stink up a storm. Mine ended up with taking showers before bed and first thing in the morning. They had a friend they really liked who lived near by and he did not bath daily. He hung at our house daily. My boys didn't seem to notice till I pointed it out the kid never bathed and never had on clean clothing. So we all talked on what to do about it. The think was that if they boy himself did not bath then likely his parents hygiene were not good either so it useless to talk to the Mom of the boy.
So here is what I did; I talked to him by himself aside and told him his lack of bathing and having clean clothing really made his smell bad. I told him I understood that he did not smell it himself but everyone that came into contact with could. He need to put on clean clothes every day and bath or shower every day with soap and shampoo his hair at least 3 times a week or preferably daily. The boy ended up telling me Mom didn't do the laundry much and the bathtub was dirty most the time with dirty clothing in it. So I explained to him what he needed to do and showed him how to use the washer and drier and how much soap to use in the washer. Well with a little help the kid did much better and over all he smelled much better. He ended up washing his own clothing from then on which made his Mom happy. With boys I've found it is best to be totally direct, kind but direct. No just hinting but direct talk. I told him he would make many more friends and no more people avoiding him. I also helped him aquire a tooth brush and toothpaste which his Mom didn't bother to have for him. I got him care packages of soap, deodorant, shampoo, laundry soap every so often since Mom was such a slacker. The boys remained friends with him through high school.
Good Luck,
Ruth