Smelly armpits

I noticed recently a smell coming from my son,he will be 6 in May, its his underarms 😮 .

I am in shock but googling it seems to be common???

He doesn't eat or drink dairy, so its not that.

His diet isn't the greatest, he is autistic and the worlds pickiest eater.

He gets a bath or shower every other day or sometimes everyday depending how dirty he gets at school .

He had a bath lastnight and I'm about to give him a shower cause my nose can't take this anymore lol.

Anyone used deodorant this young? I heard Tom's is good??