Thank you all.
The problem with the solo photo was whether it was of the father in WW1 or his son in WW2. The name written on the back of the photo was the son. I think whoever wrote that must have made a mistake.
The problem with the other photo is that it is supposed to be of Peter with wife and child and the image looks like WW1 or just after. But his only daughter was not born till 1928. She looks 3 or 4 in the photo, and I doubt a man would dress in his WW1 uniform for a photo in 1932. Peter looks really very similar to his brother Tom who also married just after WW1 but he never had a daughter.
So, perhaps I need to search to see if Peter's wife already had a daughter when he married her. Although she was unmarried and not a widow at the time of marriage.
Thanks for your help