Possible Clues:

• How yellow to sound so sheepish about the girl!
• How yellow to sound so sheepish about Nan!
• It's not 7 down and not from 15 across yet is one of a bunch
• What a yellow way to forbid a letter!
• What you can get 8 down makes you sound sheepish about Nan
• That sounds so sheepish, and so yellow, about the girl
• Cream-pie flavor
• Comedians slip on its skin
• Treat for a monkey
• Crazy to discard small piece of fruit