Dear Martin,
If your interest in Leslie Haden-Guest should ever extend to his later life, you're welcome to get in touch. I've been working on Edith MacQueen (1900-77), who became his third wife in 1944 (and thus was granted probate on his estate when he died 1960). She's interesting to me as a pioneering university woman (she got a PhD in 1927) who went on to work for the BBC, see
women-historians.wp.st-andrews.ac.uk/202...edgar-macqueen-ph-d/
Her papers are held at the University of St Andrews, but they're mostly research-related rather than personal, and if there is any L H-G material in there, it's not obvious... I have found a couple of letters from him, on her behalf, in another archive, but not likely to be of interest to your current research.
I'd also be interested to know if your branch of the family should happen to have any stories about Edith MacQueen - especially photos! - because I have far less information about her life after marriage (and after her widowhood) than before...
Best wishes,
Aileen Fyfe, University of St Andrews