Should my step daughter kiss her dad on the lips?

I agree.  We went to a therapist when we got married, just to help blend our families.  However, the kissing issue wasn't discussed..but, at that time, it had onlyhappened the one time and I assumed he was still in agreement it wasn't cool and was going to address it with his daughter the next time she tried to kiss him on the mouth.  The therapist did touch on my stepdaughter's most likely need to protect her dad and for us to notice how she will find ways to remind him she is his number one girl.  The problem is that my husband now is fine with her kissing him on the mouth and let's it be known she is the center of his world.  My husband swears I am just jealous of her and I need to get over it. I don't think I'm being petty....this is a new behavior and I feel like she is old enough to be told, especially if he felt uncomfortable with it.