Legally, yes, they do have the right. But, politically, it's touchy and you'd have to be a cold SOB to not feel a thing if you do it. Reality is, 18 y/o is really a very tough age to be simply thrown out. And, the child needs to be given prior warning, otherwise it's simply cruel and unjustified.

If they're in school, then it may not be justified. Going to school while working makes things way too hard.

OTOH, if the child is working and doesn't want to go to school, then it could be justified. Again, with prior notice and making sure the kid has a plan.

>Have right to reproduce
>Have right to relieve yourselves of the consequences of reproducing if things don't go your way

Wow that works out pretty well doesn't it? You have the legal right to pass your needless, meaningless suffering onto the next generation.