Jenny (Human Nature TV character)
From Tardis Wiki, the free Doctor Who reference
Jenny was one of the cleaning staff at a boys school in England in 1913. She became good friends with Martha Jones, who became a maid to look after the Doctor, who had gone into hiding as a human.
She was always cheerful and screamed when she was excited. Jenny was captured by the Family of Blood and her mind was consumed by the Mother so that she could possess Jenny's body. (DW: Human Nature)