I think as long as you don't harrasses them if you emailed her and she didnt reply try once more then leave it. Maybe she just wants to keep him to herself etc and thinks you may want to come see him etc or your checking up on him.
I don't want her to think I'm going to bother her or even go visit him because I'm not. And if she sends pictures of him, I'll probably never email her again. It's just when I originally got him last October, he was very unhealthy and already had his winter coat, and so when I gave him to her I never got to see what he looked like shed-out or see him at his full weight.
Also my horses old owner really really annoys me wanting to see her, ride her, visit her like she still has something to do with her soo I igniore her requests as its my horse now I don't want someone coming down to my horse and thinking they did better etc