2 year olds can be pretty quick. And fearless. This entire situation probably played out very quickly. I won’t pass any judgement onto the parents without details.
Seconded.
Mine were taught long before age 2 that when I said “hot” then they’d better stay away from whatever. Their little minds never forgot. I’ll give you that some kids can be stubborn but that’s no excuse. Parents need to be the parents and keep them and the dogs inside when dad is mowing or using other potentially dangerous tools.