Since I heard from you I have had the opportunity to talk to my mother and father - my dad's mother was Eva Scarrott who was, I think, a niece of Lexden's.
My mum has a vague recollection of someone visiting Eva somewhere around 1949-53, possibly from Australia, who may have been called Cecily or Cicely.My mother thinks Eva may have given this person a painting of Lexden's.As you can tell, older memories are not working too well!
I don't know whether any of this rings a bell or not?
More generally, I can confirm that Lexden had at least 3 daughters and did paint particularly large pictures - often near life-size.I certainly remember a large picture my grandfather owned until his death, and my parents have another large painting that remains coveted by their family!
I'd be most interested in whether you are able to shed further light on this.