And what if their other half is genuinely a bad influence on them? As a parent it's difficult to deal with because you just want the best for your kids, but as the old saying goes, sometimes love is blind.
I want to get along with my kids' partners (who could potentially go on to be their spouses) because if you don't it can have a lasting impact with resentment setting in and families growing apart.
My wife's dad must have wondered what he'd struck when I first turned up on the scene wearing blue nail polish, piercings galore, and long dirty hair. And while that sort of thing is only small aesthetic stuff, my father-in-law - whose a good salt of the earth bloke - didn't give a hoot about it and treated me (blue nail polish and all) like his own son from very early on in our relationship.
But oh how times have changed and now it's me worrying about what my girls are going to get up to - and with who.
The thought of them negotiating the highs and lows of relationships makes me want to sit down and write them a dating manual. Don't worry, I won't. That would be obsessive.
After all, just like their mum and dad before them, they are bound to make some stupid mistakes, and no doubt they will bring a few drop-kicks home, but basically you've just got to be there for your kids.
The tricky issue I'm hoping I never have to deal with is if one of them starts going out with a much older person. When they reach their 20s, fine, they can do what ever they like - and who am I to say anything at that stage anyway. But while they are still in their
teenage years I hope they have a wondrous and fun time rather than growing up too quickly under the influence of someone older and more mature.
More inevitable is having to tackle the issue of what age it is appropriate to be having sex? And then all the off shoots of that such as: is it better to let them stay together under our own roof? Because if not, where will they be off doing it? The local bowling green after dark?
But like I say, thankfully it's going to be a few years before I have to deal with all this. Though I suspect these issues will creep up on me faster than I think.
Now then, where did I put that application for a gun license?