Hi all,

I am trying to find out the name of a horror movie i have seen in the 80's.
The story was about a family which on a stormy night hears a knock on the door, when they open the door there see a women (i think she was pregnant).
they let her sleep for the night and in the morning they see she gave birth to a child and the women disappeared. they raise the child and this child kills all the original kids of that family.

PLEASE HELP. I HAVE SEARCHED EVERYWHERE.
CAN'T REMMEMBER THE NAME.

THANKS.