I think MikeS is right. Sometimes it takes a while to figure out just which was which. Will contain spoilers for the last two storylines:
In RT, Julia came into the past and Ben was living at Collinwood and found her and helped her. Carrie was his granddaughter, and so lived there, too, and presumably continued to live there after his death.
In PT Carrie was psychic and some of the Collinses went to the cottage to try to get her help. It apparently had also been the meeting place in their past of Amanda Collins and her lover (Forsythe?).