Captain von Trapp played by Pete.
Captain von Trapp is a retired Austrian Naval Captain.
Pete is an old friend of Jim's. Jim invited him along to join in this new game. Pete designed a character to maximise all the skills he thought would come in most useful in a World War II era game, at the cost of being a widowed, retired sea captain with seven dependents and no social skills.
Fräulein Maria is training to be a nun, and working as governess to Captain von Trapp's children.
Fräulein Maria is played by an acquaintance of Ben's, who attends his drama classes. She was interested to come along and see what this "roleplaying games" thing was all about, after Ben described it to her as a sort of improvisational acting thing. She is dedicated to playing her character as a real, complex person with motivations inspired by a well-considered backstory.
Liesl played by Sally.
Liesl is the eldest von Trapp child.
Sally is Ben's younger sister. Ben took her along to the game on the first evening when his parents couldn't get a babysitter for the night. The GM quickly gave her a character to play so she wouldn't get bored. She enjoys the make-believe aspect of the game, but has some trouble separating it from reality.
Friedrich played by Jim.
Friedrich is the second oldest von Trapp child.
Jim is a rather gung-ho roleplayer, interested in action, cool fight scenes, and lucrative spoils over careful consideration or puzzle solving. He frequently acts before he thinks, which includes fixating on his own strange explanations for setting details that the GM hasn't explained yet.
Kurt played by Ben.
Kurt is the fourth oldest von Trapp child.
Ben is a thoughtful roleplayer who tries to think through the best course of action within his character concept and the setting. He enjoys coming up with clever ways to justify the success of his plans within the premises of the setting.
Louisa is the third oldest von Trapp child. Her main concern is recovering the mystical Lost Orb of Phanastacoria, a powerful occult artefact, before Hitler's occult researchers find it.
Brigitta is the fifth oldest von Trapp child. She is 10 years old, and was elected to put a frog in Fräulein Maria's jacket due to her great wisdom and popularity. How exactly she gets away with this is a mystery.
Marta is the sixth oldest von Trapp child. Captain von Trapp trusts her implicitly, but Friedrich suspects Marta is up to some sort of nefarious plotting behind their father to take absolute power into her own greedy hands. Who is right remains to be seen.
Gretl is the youngest von Trapp child. As such, part of her job is to keep her father out of trouble, which seems to be a very difficult thing to do with her brothers and sisters around.