Possible Clues:

• 'The Sound of Music' name
• 'The Sound of Music' family name
• "The Sound of Music" family name
• "The Sound of Music" name
• Von ___ family ("Sound of Music")
• Maria von __, family singers' matriarch
• ''Sound of Music'' surname
• Surname of a family of Austrian singers in 'The Sound of Music'
• Pound, as potatoes
• "The Sound of Music" family