Sherral, I can imagine you feel bad, you are such a warm and caring grandma (and a person in general!), but everybody knows it was an accident and nobody would ever blame you, these things can happen!
Your granddaughter is such a cutie! I´m sure she will recover fast and well!
Sherral, in years to come she will laugh about it with her friends!!! Plus she'll be really cool - i've never had a broken anything, and all my little friends at school used to think I was really boring!!!
Seriously - don't beat yourself up - accidents happen, and although you feel really bad about it, I sure nobody is blaming you.
Chin up, gives you an excuse to spoil her even more now!!!!