Kids say the darndest things

I picked Lucas up from school today and asked him how his day was. He told me that they went outside and it was too hot for him. It was 85, but whatever. If the sun is out he thinks it is hot. He then proceeds to tell me that his teacher Ms. Beth was not at school today because she had to go to the Dr. And finishes the sentence with " it's OK, she's not going to die"
HUH??? Where did that come from? I asked him if he knew what it meant to die and he said no. I tried to explain it to him, but by this time there was a firetruck and his attention had been redirected. Some of the things he says just crack me up, I don't know where they come from.