Shaun.
Peoples personal accessories continue to be worn for years so, watches, watch chains, studs, pins, and a range of woman's acessories can often help identify a subject, over a range of photos. And some times even down the generations.
If you have other photos to compare with, it might pay to ask your Mum to rescan the photo at a high resolution and then crop to just the individual accessory, to keep under the posting cap of 500KB. That way we should be able to see more detail, in each acessory, to help the identification process.
In our family case, unfortunately one local history publisher reversed a photo in print, so the photo credit incorrectly named the siblings. Rt to Lt instead of the other way around. As same named cousins were united in marriage, it was hard enough sorting out the individuals in the large familles, without the added complication.
Many extended family since have incorrectly identified the siblings when researching.
The proof of the identity of the subject is Gt Grand Ma's broach that came with her from Scotland to NZ in 1859.
Regards,
Alan.
