My pitch for a sequel

OK. "Ghost 2" would be about a widowed middle aged man with two grown up daughters who all witness a murder on the way home from his retirement party. He gets killed but the girls get away.
They're put in the witness protection program but the gangsters are still after them - so the father who's now a ghost tracks down Oda Mae Brown who's now hosting a Cable TV show about contacting the spirit world. In much the same way she agrees reluctantly to help - thinking Sam Wheat would have wanted her to.
The bad guys would be corrupt police officers and the criminals obviously.
Toward the end - Molly's character would come into the story. She'd help Oda Mae hide the two daughters or something. We'd find out (and this part is important) that she found someone else - got married and had kids.

Only rough ideas here - but I do think a sequel could work.