So sad. Accidents happen so quickly. My 15 year old almost died from a bike accident last summer. Simple error on her part,and hit a bump in the sidewalk just at the wrong angle, and head over handle bars.
Helmet saved her life, She did suffer other major injurys and was out of commission for 6 weeks, fortunatly she wasn't anywhere near the road when she fell.
My heart goes out to the family.