My pamangkin has body odor even though naliligo naman sya at nag-aapply ng deodorant? What to do?

I have a cousin who has the same prob (she's a girl) what her mom did is let her use deo for men and it was effective. mas concentrated kasi for men cos u know mas active kasi. pero baka boy ang pamangkin mo so this doesnt make sense haha! Did s/he try tawas na? May natural and mas effective