The House On Telegraph Hill (1951)

After barely surviving a Nazi concentration camp, Victoria assumes the identity of a friend who died there. She arrives in San Francisco to see "her" son just as the boy's great-aunt dies leaving him a large inheritance. Victoria falls in love with the boy's trustee, Alan Spender, and moves with him into the aunt's mansion on Telegraph Hill. However, she finds that living life under an assumed identity is fraught with pitfalls.

IMDb: https://www.imdb.com/title/tt0043660