This is the same family as in photograph 2, taken a few years later. Although dad is wearing the same spectacles and perhaps the same hat, the baby has grown into a toddler.and the little girl has grown too, though still has the same twisted smile. The little boy also seems to have a slight twist of the lips. Nice sun hat, and I like dad's pocket of pens (there may be a pipe stem in there as well!). Can't make out what his octagonal badge reads (the nearest I've got is Auxiliary Coastguard). Mum looks a little careworn now, and her leg is bandaged. There's something in her right hand that I thought at first was a bulb shutter release but I think is probably a small bottle or toy? The boy's shorts appear to be kept up by buttons on his shirt. That's a great idea which would avoid "muffin-top!"
In the background is a group of women and girls dressed in white. I wonder if they are dancing? And note the rather large derriere captured in the middle-ground!