Anyone else already feeling jealous/protective?

I feel like a bitch but sometimes i can't stand the thought of certain people holding my baby. One person in particular who shall remain unnamed lol They are family but I don't particularly trust or respect them but they are over the moon about a new baby coming. They post on Facebook about the baby and make comments about what they can't wait for and all their expectations for how things are going to be. I want to shake them and remind them it's my kid not theirs. To me it's coming across as obsessive, but I know they are just excited. It still worries me though. Considering I live with this person in their home it's uncomfortable for me. I know I need to get over it and let them know when they overstep boundaries. 
Anyone else feeling this way?