Dear Linda,
Thank you so much for getting back to me. This has been a real challenge! I instantly disliked the pose of the girl in the photograph but loved the boy! Given that, I decided to give it a try.
I also took lots of extra reference shots to help me but the age gap was obvious, so consequently they weren't much help.
The painting is now propped up in my studio where I am 'living with it' and hoping that inspiration may come one day, however, I agree with what you've said, and the typical studio pose is what the biggest problem is, in addition to this, I don't think he was a particularly good photographer because the lighting is obviously in the front.
I have worked on it a little more and tweaked in a few areas, I think that it is nearly the best that is possible given the resourse photograph.
No Linda, you haven't discouraged me at all, you have really just confirmed what I already thought.
Thank you for taking the time to look and comment, it is much appreciated.
Barbara