If it is your lot to deal with such a situation, please tread with care, for the sake of everyone involved. First, consider the delicacy of some of those who cannot bear the thought that such things ever happen, especially in their family. In regard to the first type of person, please use a certain amount of restraint when it becomes necessary to explain the facts. Don't ignore them or seek to hide them, but don't proclaim them proudly if the news is likely to offend. As for the second attitude, I agree that no child should be burdened with the guilt of his or her parents.
Babies come to both the married and the unmarried.
They all deserve to be loved. In cases where the father is known at the time of birth, the fact is often mentioned in the parish register or civil record. This is an invaluable aid to us as we try to reconstruct the details of our family connections. Given the apparent widespread occurrence of births out of wedlock in these locales, such registers were a necessity to maintain order in their day, and they can be invaluable tools in our day as we seek to establish the facts of our own descent. Similar documentation can be found in British court records, where we can read of men being brought before the court to admit to their roles in local births out of wedlock.