This is one of a number of autographs from the same collection. They have been stored in a garage for a number of years and some have related faults and/or are a bit marked/dirty - see the images in this listing and my other listings.
A further example of Kay Kendall signing can be seen here : https://www.memorabilia-uk.co.uk/p/kay-kendall and Rex Harrison here : https://www.historyforsale.com/reluctant-debutante-movie-cast-autographed-inscribed-photograph-co-signed-by-kay-kendall-rex-harrison/dc176246