Squadron Leader Stan Duff 23 squadron

Hi all,
I am trying to contact any relatives of Squadron Leader Stan Duff who flew with 23 squadron during the Battle of Britain.
I would like to speak to them regarding Laurence Karasek who flew with him on several occasions during 1940 and lived near my home in Bexleyheath.
If anybody could assist me with this I would be most grateful.
Cheers
Gerry