Find the Hidden Tonks
Andromeda Tonks looked at the array of children in front of her with dismay. She was spending some time with her cousins, the Weasleys, and had been tracking her own daughter by the fact that Nymphadora was the only child there with black hair.
She should have known better than to assume Nymphi would stay a brunette. Not when she was surrounded by a sea of redheads.
"Nymphadora! It's time to go now!"
This resulted in a lot of giggling, but no answer from Nymphadora. Obviously it was a case of "find the hidden Tonks."
There was only one thing for it. "I can make my ears wiggle, can you?" Andromeda challenged.
The Weasley children concentrated hard on wiggling their ears.
Nymphadora, of course, immediately grew bunny ears, as they wiggled better.