Would one half can beer kill a 3 year old child?

It's extremely unlikely that one half can of beer would kill a three year old child, as the alcohol content would not be enough to cause life-threatening symptoms. However, it's important to keep in mind that the effects of alcohol on a child's developing body can be severe and children may respond to alcohol much more intensely than adults.

Even small amounts of alcohol can cause changes in breathing and heart rate and it can also lead to choking or alcohol poisoning, even at modest levels. For these reasons, it is certainly not recommended to give alcohol to children.

If a child has consumed any amount of alcohol it's important to seek medical attention immediately, just to be on the safe side.