Little girl at daycare is possibly infatuated with my son

My son is a little over 2 and this girl is around 3. They are both in the same toddler room at daycare. Today when I picked him up, she ran over to him when I was helping him change his shoes / put on his coat to give him a hug. They hugged and then she gave him a kiss on the lips (he was reciprocated). She kept hugging him and kissing him on the lips (another little girl in his room even came over to give him hugs) until myself and their teacher had to ask the girls to leave him be as he got ready to go. Even when we were saying goodbye and ready to walk out, she ran over again. They'd like hug him and try and lift him.It was cute (the hugging is sweet) but this happens pretty much every single day. For a while at first he didn't like it and would push her away and say "no" and we'd have to gently remind her that if he says no then we have to respect his boundaries, etc.My husband tells me she gets dropped off around the same time as our son in the morning and she's "all over him" then as well.The main issue I have is the kissing on the lips, particularly because of spreading of germs (I know kids are germ carriers as they are but mouth kissing is pretty much a guarantee of transmission of germs, getting sick, etc.)My question is... is this normal? For a 3 year-old to have a crush? Seems silly to me. This is our only child so this is all new to me. I might have a chat with his teacher about this. Really I'm not sure how I feel. I think it's sweet he has some buddies at daycare and being nice to each other, but the obsessiveness of it is creeping me out a bit! via /r/Parenting http://ift.tt/2eZ7CzA