No one else is gonna take a crack at this? Okay, I will. I think thats a great idea. Of course people are going to have relationships and more likely than not travel together. Thats only natural. I hadnt thought about having a family like that in a game before, but I can see how that could be interesting. I really didnt like how useless getting married was in FO2. It was a purely negative experience. Apart from getting laid I suppose. If your partner could be more like any other companion I think that would be cool, I might enjoy that in the game.
Then theres the issue of the children. I think that could also be cool, but yeah, I can see how the ability to kill these children would cause a bit of controversy. I dont think it would neccisarily bother me, but I dont think something like that should be implemented because it would be too contreversial. Perhaps there could be children but they would serve no purpose in combat and not be attacked.
So I dont know, maybe they wouldnt be your children but I think young companions would be cool. If you become a knight in the BOS maybe you could have a paige or a squire or something like that. Someone to help carry equipment and such but not partake in combat. There would be a lot to consider, but I like the idea.