I'm sure someone else has probably said it already, but I'm too lazy to read the comments. So here is my 2 cents:

I have two daughters. I adore wearing makeup (I used to model until I realized I want to be a nurse, so it kind of comes with the territory, but I also have some heavy depression that makes me feel shitty). My husband HATES the idea of them wearing makeup and wanting to wear makeup because of how it will make them seem too "grown up".

So we have a compromise. I teach them that, while mommy wears makeup, it isn't because I HAVE to. I wear it because it makes mommy happy to look like a doll (because all of their dolls have makeup. they're kids, not idiots. They noticed this fact) and that sometimes mommy feels that makeup helps to make her feel better when she's sad.

The compromise is that I can allow my girls to wear makeup that is beneficial to them in some way so long as I explain that they are already beautiful and restrict colors to ultra light and/or sheer pinks and purples. So they have tinted lip balm with SPF. They have nail polish in kiddy colors (usually from those sets based on fave movies/TV shows) that, when they start to chip and grow out, that signals me to cut their nails again, otherwise we get scratched up by sudden claws because their nails grow stupid fast...literally cutting down talons every damn week! They get to play with eye " shadow ", which is my own little recipe of a facial moisturizer that I tinted with some of my poorly pigmented, drugstore brand, pink eye shadow.

My husband hates that his little girls want to wear makeup, but we agreed that if we taught them that they are already beautiful and that the makeup is just to help you feel the way you already look, then it's OK to let them use things that are beneficial to their skin (with supervision, otherwise it gets messy!).