What ever happened to Nanny Carrie's son?

In the episodes right before Crazy Carrie dies they mention how she had a little boy. What ever happened to him. What if the father of the baby is still alive and comes back for revenge for killing Carrie. I feel that the writers should tell us what happened to her son and give us a background on Carrie. I wonder if Carrie's son's father is as crazy as she is. I think that maybe the robber has something to do with Carrie.