Gone but not forgotten

I'm staying with my mum for just over a week and she always likes to have a bit of sort out while I'm here. She doesn't have much she hasn't sorted already, just a few gems like this photo tucked away. It was in a frame and she hadn't realised there was writing on the back. It was originally my nan's photo.
Gordon was my mum's cousin from Wales. She stayed with his family for part of the Second World War. His plane went down when he was on a training mission with a trainee pilot.
I never met my Nan's sister, Gordon's mum. Mum has tales to tell of them though.