Did I Kill Mrs Tittlemouse? :(

How did this happen? :(

Did I throw Jazzy dog's ball too hard and take out Mrs Tittlemouse?

This is how we found it, on top of Mrs Tittlemouse. It looks like I have staged the pic but I promise that I haven't.

"We shared in one delightful house;
We shared a mossy bed.
I never knew another mouse
Than her – and she is dead.
The beady eye, the nimble strength,
The soft and silken fur!
The whiskers, and the noble length
Of tail that followed her!
And now I’m lonely in the run,
And lonely on the stair,
And lonely in the nest we spun –
So warm when she was there!
The wheel she loved to turn is still.
The feet that ran so light
Have twinkled up the heavenly hill
And tread the wheel of night."