Hi.
I saw this movie (or it might have been a TV movie) about 30 years ago.
From what I can recall, it was in colour and it involved a family on a train having their bag swapped around with another passenger’s, and one of the bags contained jewels or diamonds. They had a child, a young girl, who seemed to be aware of what was happening but no one believed her until the end.
Any and all help very welcomed; it’s been annoying me for years and not a person I know has been able to identify this film!