Ladies, help!

How do I tell a parent to bath their child on a regular basis. She arrived at 6:30 this morning and was quite obviously filthy dirty. My daughter and I used almost a package of baby wipes cleaning her off. She walked onto my mats and left black footprints all over my house.

Last week she came to daycare with the same lipstick mark on her face for the entire 5 days. I purposely didn't wash it off after lunch/snack just to see when she would be bathed again and it was there the entire week!

The week before that she had a dirt ring around her neck...so gross!

I don't want to be rude, but I'm tired of spending so much time washing her off so that she's clean enough to come into my daycare room...how would you ladies phrase something like this with the parents???