How do we politely tell my father in law and his wife that we don’t want visitors as soon as we walk into the house when we get home from the hospital?

The reason I’m preparing myself is because they literally were in my driveway as soon as pulled up to my house with my first.

I don’t want to come off as a nasty b**** but if I don’t say it the right way, they won’t get it. Also, my parents are watching my daughter who are coming from out of town so I don’t want them to feel like they are being pushed out from my in laws who live five minutes away.

Thanks!!!