Wow thanks so much everyone for your comments - that is a massive help!
I agree the people with the baby look too old to be the parents - however this photo is believed to be taken either in 1858 or 1860 - as the baby is believed to be either the youngest or second youngest child of the couple. Agnes was 40 when she had her last child - she was born in 1820, and William in 1806. She had an extremely harsh life (came to the Female Factory, Hobart as a convict), William was also a convict. They both had to survive dreadful conditions and after they gained their freedom they were faced with all sorts of challenges.
So it is enlightening to know that the photo can be identified as around 1860 due to it being of a particular type! It means that the people cannot be of the next generation down, at least.
We weren't sure if it was Agnes or one of her daughters, but if it was one of her daughters, then it would have had to have been late 1800's rather than middle... so this is very exciting as it means it is very likely to be of Agnes. She was an incredible lady with an incredible story... she started life as an street urchin orphan in Glasgow, Scotland.... got caught for petty theft (just trying to survive)... transported to Australia... in and out of the female factory, found herself pregnant... but managed to survive all this... afterwards, she and William lived on the land and worked hard to support their growing family. They ended up with a family who managed to establish themselves well.
I think the photo of Agnes on her own must have been taken later, maybe in the 1870's.... she died in 1877... so only aged 57.. which is much younger than she looks in the photo - but it is hard to tell, not being very clear, and as covered up as she is....
It couldn't be her mother or anyone of the previous generation as they weren't around... so it does seem to add up, notwithstanding how old she looks in the photo.
