When should i start letting my child use deoderant?

Body odor : Adolescents should start using deodorant when they begin having body odor. Usually this will be within a short time of beginning to develop "adult hair" (underarm, pubic, etc.) and is a normal part of puberty.

Be practical: The axillary odor producing glands can become active before puberty with hormonal input from the adrenal glands. Some increase in darkening and thickness of axillary and genital hair will occur at the same time and this can precede puberty by more than a year. If they stink, let them use deoderant, and don't worry if it's too soon.If they don't stink, humor them, it will come soon enough.