Carmen (Planet of the Dead)
Carmen was a middle aged woman, married to Lou, who was onboard the London Bus Number 200 with the Doctor and Lady Christina de Souza during Eatser time. She was seen to be a caring person to the other passangers and towards the Doctor when she worried for him to be careful after giving him a prophecy. She also seemed to worry quite a bit.
Carmen had low-level psychic abilities. She was able to predict future events (every week, twice a week, she and Lou would win ten pounds on the lottery), sense what was going on without her seeing it, and hear the voices of the dead on a planet. After the bus went through the wormhole to the planet San Helios, she warned the Doctor and the passangers that something was coming, riding on the wind, something that devoured. the After the Doctor saves her and they return to Earth, Carmen tells him a prophecy: "...your song is ending, sir... it is returning through the dark... and ... oh, but then... he will knock four times." (DW: Planet of the Dead)
Her prophecy later comes true when the Doctor realizes that "it" is refering to Gallifrey returning through the dark, through the Last Great Time War, and the "he" is Wilfred Mott, knocking to get the Doctor's attention. Just like her prophecy predicted, Wilfred's knocking does ultimately lead to the Tenth Doctor's death, in which he become the Eleventh Doctor. (DW: The End of Time)