Symphony Stream and Harmony Lake
From Tardis Wiki, the free Doctor Who reference
Symphony Stream and Harmony Lake were two "sassy and dangerous" friends of Amy Pond and Rory Williams, who were enlisted to help them and the Eleventh Doctor in their search for baby Melody Pond.
One of them was dark-skinned with black hair worn in a ponytail, while the other was light-skinned with blonde hair. It was not specified which girl was which. (NOTVALID: Doctor Whoah! 440)