Former Blue Peter presenter John Noakes, who used to host the show during the 1960s and 1970s, has died at the age of 83.
He had been suffering from Alzheimer's disease.
John was Blue Peter's longest-serving presenter, appearing on the show from 1965 to 1978, and often seen with dog Shep by his side.
Blue Peter presenters always get up to lots of adventures on the show and John was no different.
He threw himself into various challenges including white water rafting, a record-breaking free fall parachute drop and even travelling up the Amazon in South America.
But one of the his most famous moments on Blue Peter was when a baby elephant was in the studio. The animal couldn't control its peeing and just wouldn't behave!
The head of the BBC, Tony Hall, said: "John Noakes was one of the BBC's most loved children's presenters. He was a warm and engaging presenter who appealed to all ages and provided children's TV with some of its most memorable moments. He will be missed by his many friends and family."