The Doctor met Wilfred in the 2007 クリスマス Special 'Voyage of the Damned' while on an excursion to Earth. However, the Doctor was unaware that he was the grandfather of Donna, who he'd met in the クリスマス Special the 年 before.
Wilfred was a confidante of Donna, as he was aware that she was travelling with Doctor in the TARDIS, whereas her mother Sylvia was not.
Wilfred stuck up for Donna whenever she was in a fight with her mother, and he would often sit and talk with her while on 'the hill' after on of these arguments.
He is a keen astronomer, and is often seen with his telescope up on the hill.
This character appears in 7 Doctor Who episodes; Voyage of the Damned, Partners in Crime, The Sontaran Stratagem, The Poison Sky, Turn Left, The Stolen Earth and Journey's End.