Winnie the Pooh was a fictional character.
Lucas Seyton quoted Winnie the Pooh to the Second Doctor when he agreed to help rescue Jamie and Zoe from killer androids. This threw the Doctor a bit, as it was usually he who quoted Winnie the Pooh. (PROSE: Fallen Angel)
When the Eighth Doctor was split into three personalities, Charley Pollard, in order to differentiate between them, decided to call the more exuberant one "Tigger" and the more irritable one "Eeyore" after characters in Winnie the Pooh. The Doctor said that Tigger was his favourite character from the books. (AUDIO: Caerdroia)
Rose Tyler tried to make a toga out of a bedsheet in preparation for her visit to 2nd century Rome. The Tenth Doctor pointed out that Roman girls probably wouldn't wear togas that had Winnie the Pooh on them. (PROSE: The Stone Rose)
Behind the scenes Edit
David Warner narrated 1997's Pooh's Grand Adventure: The Search for Christopher Robin, 1998's A Winnie the Pooh Thanksgiving, and 1999's Winnie the Pooh: A Valentine for You.
The 2018 live-action film Christopher Robin featured Peter Capaldi as the voice of Rabbit, Sophie Okonedo as the voice of Kanga, and Toby Jones as the voice of Owl, along with Hayley Atwell, Mark Gatiss, Adrian Scarborough, Roger Ashton-Griffiths, Amanda Lawrence, and Paul Chahidi in live-action roles.