Unwanted family

I have people in my family that have never had anything to do with me besides a quick hey if I run into them somewhere but as soon as I had my baby now they all want to be involved and have even shown up at my house unexpected to see my son after me trying to just ignore them.

I don't want them around because I know it's just a "Facebook" attention thing and it will stop as soon as the "new baby" faze where's off.

How do I stop this?