Seen in sister's garden in Burgh Heath, near Banstead, Surrey.
She has never seen one ever before in the area.
Is this unusual?
Fairly unusual. Not the rarity it once was of course due to the reintroductions but Red Kites are quite lazy about spreading out from their introduction areas and so it remains quite scarce in Surrey, certainly compared to Buzzard which has become much commoner. Red Kite is not yet on my Surrey list.