Simplify the following text for a Grade 8 native English-speaking person.
Original: However , in the 2005 film adaptation of the book , it is implied that he is upset that their father was forced to serve in the war and that they are sent away from home as a result .
Simplified: However , in the 2005 film adaptation of the book , it is said that he is upset that they are sent away from home , on account of their father forced to serve the war .