Date wise I don’t know that there is much fashion wise to determine if this little cherub is your mother or her sister.
I initially thought the little boots might be earlier and indicate it was the sister but they could be hand me down shoes anyway as you say the family were not wealthy.
The little girl looks very well turned out though.
Maybe one of the dating experts will spot something to help.
Do you have any photos of your mother as a young child for comparison?
Age wise I think she could be 14 to 18 months, though I am not confident with that estimate. Grandad could be in his 30s or 40s. I am not confident about that either.
