sublimated wrestling singlet

Hi, what size do I need to order if my kid is 60kg and measures 40cm for 1/2 chest?

Should a female wearer go up a size in this? Weight wise fall in the middle of one size but concered about room for curves if it tends to run small. Thx!

I’m 5’6 at 165 should I go for the M or the L

I want to buy one buy you guys dont have a medium size please make one and ill buy it!?