Photoshop.............1940's Style

This is a pic of my mum, dad and older brother.
It was taken in 1943 (?), my dad had his taken while on R&R in Durban ( leave from Burma ), he then sent the picture to my mum who in turn toddled off to a photographer's studio in Glasgow.........with pic of hubby in hand.
Seems picture of mother and son was duly taken, pic of dad added on to end, and whole thing photographed..............................Hey Presto! through the wonder of photography, everyone's together.
Crude now, but effective for the time!!