So we're now in a parallel universe where humans reproduce like plants. There is a person-seed season where the person seed plants let the seeds go and they fly through the air looking for things to catch on to. During this season, if you want a baby, you normally wash your house thoroughly paying special attention to any soft porous surfaces and making sure everything is clean and safe. You then open all your windows and let the seeds blow into the house, hoping that one will settle into your couch's throw and start to grow into a baby.
However, your neighbors are terrible, lazy people. They didn't even realize it was person-seed season, and didn't pay attention at all to the careful cleaning of their home or disinfecting of their couch's throw. In fact, they've had parties every weekend and their house is overwrought with beer bottles and paper plates. They left their windows open and a person-seed got in, and began to grow, in this terrible, irresponsible environment.
Do your neighbors have a right to dig up and throw away that person-seed? What should happen to it/them?