My little sister is wearing too muh makeup?!?

My sister 11 years old and is wearig the whole deal to school. Today, I think she wore tons of brown mascara, brown eyeline, a weird dark shade of eyeshadow that went all the way up to her eyebrow, and piles of blush and lip gloss. Personally, I thought she looked like a freak. What should I do? And forget about talking to my parents. They just encourage her more. Thanks.