What were the seven names in sound of music?

The musical "The Sound of Music" features the characters of the von Trapp family, who are named:

1) Georg von Trapp

2) Maria von Trapp

3) Liesl von Trapp

4) Friedrich von Trapp

5) Louisa von Trapp

6) Kurt von Trapp

7) Brigitta von Trapp

8) Marta von Trapp

9) Gretl von Trapp