three possible answers. First, she may not be in season. Second, the stallion may not be emmiting semen. Third, there is a chance she may be sterile.
No it is not possible biologically for a human to impregnate any other species or viceversa. So to answer your question simply, "No a boy cannot get a female pony (mare) pregnant."
mare
A mare.
Bony Pony or Spare Mare
bony pony spare mare
It means that the mare is pregnant.
Stallion is the male, and the female is a mare.
From a stud.
Mare
Polly "Perfect" she is a beautyful mare. The pony from my little pony GREAT ANSWER!YOU ARE RIGHT!!GOOD THINKIN!!!!
Yes. Same pony, different names.
horses never get pregnant, its the mare who gets pregnant.