Daisy Armstrong

In Murder on the Orient Express, Daisy Armstrong was the daughter of Sonia and Colonel Armstrong. She was a sweet, happy child, with lovely curly hair. She was adored by the entire household, including the servants. However, when she was three years old, she was kidnapped, and later killed.

Murder on the Orient Express (2001)
Daisy does not appear in person in this adaptation, but she is seen in a photograph and in old videos. She was described in some news footage as a vivacious and enchanting child. Unlike the novel, in this adaptation she is seven years old when she is kidnapped and killed.

Agatha Christie's Poirot: Murder on the Orient Express (2010)
In the 2010 adaptation, Daisy was five years old when she was kidnapped.