In the book "Murder on the Orient Express" who was Susanne?

tre, I think Susanne was the girl who looked after Daisy Armstrong and killed herself when she was suspected of having taken part in the kidnapping. I believe her father was the conductor on the Orient Express and also that she was engaged to Hardman who was the chauffeur, but was masquerading as a private 'tec on the train. Susanne's death was their motive for killing Ratchett.