Catherine Welch, in The Little Dauphin (1908) gives a résumé of the various sides of the question.
Luke Welch leaves to become a housemaster at More House School in Surrey which specializes in children who have difficulties associated with dyslexia.
Includes a black and white photographic portrait of Denton Welch in 1937.
Lovato was not sure which dancer it was, but decided it must have been Alex Welch (who, incidentally, had not even been present for any of the festivities).