Fatally delicious

Here I'll relate a tale from the weekend that is a parent's worst nightmare:

We bought a bag of marshmallows because we were thinking about having a fire in the outdoor fireplace/chiminea if the weather didn't get in the way. It turns out that both the weather and renovation projects prevented us from enjoying the roasty goodness of marshmallows flambe, so late Saturday afternoon I decided to crack open the bag anyway. My son was walking into the kitchen at that moment, so of course I had to give him one. He left the kitchen with it, and as he passed my bedroom my husband called out asking what he was eating. He answered with his mouth full of marshmallow, and his dad asked him to go get him one, too.
As he was walking back out to the kitchen I noticed that he had a funny look on his face, and then I saw his hands go to his throat. I called his name, and saw that when he tried to answer, there was no sound coming from his throat and his face was turning red. I said his name again, and this time there must have been an edge of panic in my voice, because my husband came bolting out of the bedroom. He grabbed our son, spun him around, and stuck his index finger in the boy's mouth and down his throat, feeling around for the marshmallow that was blocking his windpipe. At first he couldn't feel it, and was just about to tell me to call 911, when he managed to pull the soggy thing out of our son's throat. It was half of a regular sized marshmallow, which had expanded, causing it to get stuck and my son to not be able to breathe.
We were extremely lucky that my husband was able to get at the marshmallow chunk, and that a very scary situation didn't result in a different, more tragic, outcome, because apparently this is more common than either one of us realized. So, for right now, full-size marshmallows are off limits, unless they have been roasted and are nice and gooey.
My son has always been a little bit of a careless eater, and we now find ourselves watching him more closely and reminding him to slow down, take smaller bites, and chew thoroughly. Of course, this frustrates my husband, since at seven years old, we feel like we shouldn't be needing to treat this child like he's just learning how to eat. Considering how the kid feels about the Stay Puft Marshmallow man (see below), I'd think that this would put him off of marshmallows for a while. But no. On Sunday evening, he asked for a marshmallow for dessert. I was hesitant, but we figured he'd learned his lesson. And what does that boy do? Immediately shoves the whole thing into his mouth! He's just determined to give one of us a heart attack, isn't he?
And to make matters worse, my poor husband has been having the "what if" scenarios running through his head since this incident - he has a worrier's nature, although he tries to hide it, and this has affected him pretty deeply. I say we're lucky, and I am not going to dwell on what could have happened, although I will change how I feel about letting that kid wander around the house with food.