I cringe at the idea of a ten year old (or eleven, twelve, or thirteen year old) wearing make up. I think that there is something inherently creepy and off-putting about adults normalizing a child walking around trying to look like a woman. In this day and age, where children are commonly exploited and sexualized by degenerate adults online, this trend is out of touch and actually harmful imo.
Additionally, what are we teaching them about self love and self-esteem? Why allow little girls to start looking at their natural faces as something to hide so early in life? What happened to teaching them that they are lovely as they are? It’s nearly inevitable that most young women will start wearing make up at some point, so I see no need to rush. Let the children be children for pete’s sake!
Gransnet rant aside, I keep my mouth shut and those thoughts to myself when it comes to how parents choose to parent. Your DIL won’t stop allowing the child to wear the make up. She’ll only take whatever you say as criticism, and it is criticism no matter how justified you feel. Let them get on with it. Their mistakes are their own to make.