You are thinking of THE SEARCHERS. John Wayne went looking for his niece played by Natalie Wood who was abducted years before by Indians.
https://en.wikipedia.org/wiki/The_Searchers
The UNFORGIVEN with Burt Lancaster is the correct one. is the correct one.
https://www.imdb.com/title/tt0054428/
The SEARCHERS is a different movie.
https://www.imdb.com/title/tt0054428/
No, I just looked it up, it was The Unforgiven. Lancaster, Hepburn, Murphy and Gish.
IIRC, Gish’s character confessed to keeping an Indian baby (Hepburn) as consolation for the loss of her own child.