Unlikely she’d get food poisoning, as that’s one of the reasons milk is pasteurized. The one GI issue I’d worry about is Bacillus cereus poisoning, as grains carry the spores, and they don’t test for it. Generally, B. cereus is about 18 hours of sheer hell, and no sequelae.
Fear Itself, listeriosis from pasteurized milk is unheard of without cross-contamination afterwards, but it’s highly unlikely in a healthy child.
Laying aside for a moment all the stuff that is within the realm of remote possibility …
Isn’t a virtual hammer-lock certainty that the OP’s will be totally fine and have no symptoms whatsoever? Like, so close to a 100% chance of coming through A-OK that it’s totally intellectually honest to call is a “100% chance” and leave it at that?
I believe so; yes.
That is, to directly address the OP:
No. There is no need to worry about it, any more so than you were worried about your daughter before she had eaten the cereal, or worry about her any time she eats anything (for all food could potentially be contaminated at all times… but almost certainly isn’t).
From the CDC Bad Bug Reference:
So sure, it could be B. cereus. It could also be lupus … but it’s never lupus.
Indeed. In fact, if I was the OP relaying that story to someone, and they came out with “Did nobody clean up after breakfast?” I’d either laugh hysterically, or smack them. Or both.
My son once hid a bowl of ice cream somewhere for 3 days and ate it (drank it I guess) and didn’t get sick afterward.
I think your daughter will be fine, especially since the milk was pretty fresh to start with 
Yeah, spoiled milk can make you unpleasantly sick to your stomach but it also tastes really really awful, to the point that, as a kid, getting some in my mouth was quite sufficient to make me throw up. I can’t imagine anyone voluntarily consuming the stuff, sticking the spoon back in for another dose. Ugh!
you shouldn’t be worried about it, the cereal is gone.
your daughter shouldn’t be worried about either, good milk will not become poison if just out for 12 hours.
Yeah, we found our son munching on a french fry one day… like a week after the last time my wife or I could remember having eaten french fries. Apparently he’d stuck on e in a toy truck or something, and come back a week later and thought “Bonus!”.
For all we know, the bowl of milk could have been sitting on the counter beside the sink waiting to be washed or something, and the kid counter-surfed and snatched it up.
the danger is for someone who likes cultured milk products (yogurt and so on) thinking “oh it’s just like yogurt”.
i know someone (not me) who did that and they were later begging for death but survived without any further treatment (except maybe puking).
I would also re-highlight this:
Milk easily reaches a stage where it tastes awful and is perfectly safe to consume, which we call “spoiled”. The fact that it tastes so awful is not actually related to anything being dangerous about consuming it. And if your child willingly downed a bowl of milk, it wasn’t even at this stage yet.
You should definitely be worried. In most cases where this has happened, it takes anywhere from 7 to 10 years for the symptoms to show up. But expect general moodiness, lack of communication, all the way to downright bitchiness and defiance. Best of luck.
More importantly, what kind of cereal was it that it hadn’t dissolved in 12 hours? I’ve seen cereals change the color/flavor of milk in 5 minutes.
Oh, & with an otherwise healthy kid I wouldn’t be to worried.
I love buttermilk, yogurt, cheese, sour cream, etc.
Spoiled milk is nothing like that. Even a good sniff of that stuff makes most people’s stomachs clench and the back of their throats glogg up
12 hours is nothing, and its just milk. Occasionally, we’re too lazy or forget to put away leftovers after dinner and its waiting on the table at breakfast. We still eat it, nothing bad happens
Exactly. Spoiled pasteurized milk is not the same as raw milk that has soured. Leaving pasteurized milk out without inoculating it with desirable bacteria will not give you a drinkable or edible product. Raw milk does sour into something edible and drinkable because of the naturally occurring bacteria in it. (Although there are risks associated with raw milk, of course.)
my point wasn’t that it was just like yogurt but that a person would assume it similar.
there are hundreds of cultured milk products. i’ve had some that were very different in terms of taste and texture, some quite slimey.
No one who smelled or tasted spoiled milk would assume them similar in a way that counts. They’re less similar than a really fine wine and a tumbler full of rubbing alcohol.
Yep.
Ever accidentally had a sip of spoiled milk?
I’ve eaten spoiled ground beef. Spoiled milk is worse.
Back in Microbiology class, there’s a dusty old lab that everyone has had to do since…I don’t know. Probably since Pasteur’s time. It involves taking “cheap” milk and “expensive” milk and preparing agar plates with smears of each and seeing which one grows more disgusting bacteria colonies on it.
The answer is supposed to be - the answer *used *to be - that the more expensive milk would grow less stuff, because it was cleaner in the jug.
Nowadays, the lab assistant has to artificially innoculate half the samples of milk so that something - anything - will actually grow and the students can finish the lab.
Today’s pasteurized milk out of the jug is nearly sterile. 12 hours at room temperature does not present a realistic risk. Any bacteria in there would come from the air, and have time for only a few hundred cell divisions; not enough for most food borne illness to reach an infective dose.
no one except at least the person i witnessed being sick.
they didn’t spit it out at first taste or smell. they didn’t have to struggle to drink it down. it tasted different but not like they had previously experienced with spoiled milk. they assumed it was a benign spoilage rather than a harmful one.