Do you think the color of the baloon was the cause?

Or pointed tatoos

I was caught in the crossfire of a water balloon fight and was hit in the nutz twice. Both times the water balloons bounced of the family jewels and burst on the ground. Both thrown by a 5 year old daughter from a 5 ft range at a prety good clip. Wife was laughing up an anurism so i threw one at her private parts and it busted like a turtle on a busy farm road.
Do you think the color of the balloon was the cause?

different balloon. the ones that hit me burst whilst bouncing on the ground

With the information that you've given me my first thought is that the balloon that hit your wife had a membrane that was under greater stress that the balloons that hit you. If the balloon that burst upon impact had been expanded to a greater volume then the membrane stress would be closer to the maximum that the material could carry, and up on impact the resulting stress from the transfer of the momentum over-stressed the membrane causing it to rupture.

TFP