Politely asking someone to wash hands

Erika
My boyfriend's parents are really bad about petting and playing with the dogs and then holding my new baby. I know it won't hurt the baby, but this is a pet peeve of mine. Especially when they touch her face or handle her pacifier. His dad is super bad about scratching his dog's ass for 5 minutes and then wanting to hold the baby. How can I ask them politely to wash their hands? Or how can hint around? I don't want to be rude, but I want to let them know how clean I am, especially when it comes to my baby. 😬