A few hours ago a very interesting auction by Tracks ended on Ebay: a George Harrison autograph in the hand of his mother (item #400953407124). I really wanted to win this item.

My maximum bid was 250$. Unfortunately someone else won it for 255$ (only 5$ above me). I really don't understand how a George Harrison autograph in the hand of his mother ends with such an expensive price while a few months ago I bought from Tracks a John Lennon autograph in the hand of George Harrison for only 167.5$ (item #400882111510)
How a George Harrison autograph in the hand of his mother can be worth much more than a John Lennon autograph in the hand of George Harrison? Can you compare the handwriting of George Harrison's mother to the handwriting of George Harrison himself? Can someone explain this to me please?