LONDON (AFP) - British actress Elisabeth Sladen, best known for her role in cult science fiction television series "Doctor Who", died Tuesday night aged 63 after a battle with cancer. Liverpool-born Sladen first appeared on the BBC show in 1973, playing the Doctor's assistant, Sarah Jane Smith. Sladen, who was married to actor Brian Miller, went on to star in her own spin-off children's show, The Sarah Jane Adventures, the latest series of which was aired late last year. "I absolutely loved Lis," former Doctor Who writer Russell T Davies, who created The Sarah Jane Adventures, said.