Dear JulieThe book you mention could be a 1937 Annual with Rupert sitting on a bridge over a stream or a 1942 Annual and shows Rupert sitting on the wall of a Castle with Bill and Podgy with scarecrow or a 1953 Annual with Rupert, Algy and Bill sitting on a fence.
They are all called "More Adventures of Rupert"
If you would like to contact me my fax number is:-
020 8658 8498 from the UK
Regards
Peter