My sister-in-law pisses me off. She has asked several times if she can kiss my 2 week old on the…

My sister-in-law pisses me off. She has asked several times if she can kiss my 2 week old on the lips and I keep telling he no because it's gross and she doesn't even have an immune system yet. Well again, she asked to kiss her on the lips and I said no and then I turn around for a minute and look back and she's kissing her. Like wtf? My in-laws just don't seem to have any respect for my wishes when it comes to my daughter. #rantover