Buffy is walking the streets of Rome and makes a wish into a wishing well. She ends up getting tranported back into the late 1870's were Wiliam is in Rome on buisness. They end up getting together and she gets pregnant. When she is finally returned home Spike remembers it because it was an event from his past and ditches the LA crew to find her. She is still pregnant when he finds her.
PS: if it helps I do remember the ending had them 5 years in the future, at least I think it was 5 years... okay so, _years. They are getting ready for Christmas at the Council Headquarters. | 
