Natalie Morrison
From Tardis Wiki, the free Doctor Who reference
Natalie Morrison was an old friend of Donna Noble.
When Donna returned home after her recent visit to a library, Sylvia Noble rang Nat. Sylvia had signed them up to attend One's no Fun, a speed dating event. Despite being married, Nat went to the event to accompany Donna, as she thought it would be "a laugh". (AUDIO: Out of this World)