So of course, people have come up with plenty of theories as to the origins of our characters survival. Plan and simple, I think its simple cryogenics. Not only does the leaked script pretty much confirm this *as everything else has been right), what else could it possibly be? Some theories have come up with two other popular theories: Cloning or Android. First let me go ahead and rule out androids. Think about it: eventually your going to get blown to bits, and as soon as that happens you will certainly figure out real quick your an android. Now for cloning, I don't think that's possible either. One vault has already covered cloning and so far we haven't seen repeat experiments. I may be wrong, and please correct me if I am.
Cryogenics also just makes sense. Your frozen, something goes wrong, and you live while everyone else dies. Your wife/husband: gone. Your child? Now that's when things get interesting. A few theories about this child is that hes either a ghoul, or perhaps he was made it in the vault and was simply awakened before you. Some have elaborated even further and said he was awoken so early, that he is now a full grown person.
Let us first examine some things. Your child will render based on the looks of the mother and father. That's a lot of work just for the baby to look different, but the same can be said for over 1,000 names being added to the game for RP purposes. I believe the child does have a place in this world. If he was frozen, could he perhaps have been awoken early and was snatched away by their mother, or someone more malevolent? My guess is no. Children are fragile. Their systems I don't think would be able to withstand the chemicals required for cryo (going off some assumptions here) or any kind of flash freezing. A counter argument to my own point was the Vault-Tech reps insistence that his whole family would fit. Though Vault-Tech never shy's away from horrible experiments so there's that.
So is the child dead? Maybe, but that wouldn't make for a very good story if we knew that right off the bat right? We gotta have something to drive us forward! Without dad leaving the vault, why would we leave? Either we may find out later our child is dead, or we fine him/her alive! Grown-up, or still and infant. Again, it all depends on how much they are willing to bend and mold science.