Irony of "The Drunkard"

"I took a longer drink and began to see that porter might have its advantages." Pg. 343
This story is disturbing and intriguing all at the same time. In the story this little kid tries to keep his dad from becoming a raging drunk. He knows if his dad takes the first drink then he will undoubtedly go off the deep end, going through all the awful stages of a drunkard. It turns out his son might have the same problem. Ironically in an attempt to keep his dad from drinking, Larry drinks the beer himself, causing him to get sick several times. Then to make matters worse, when his dad tries to take him home, he creates a huge scene, including songs and expletives screamed at neighbors. The true irony is that the son has become exactly what he was trying to prevent his father from becoming. However, a big and disturbing shock was that his mother actually praised him for his actions. She even calls him a guardian angel. My question is, what parent praises their child for getting drunk and making a fool of themselves? Maybe she just valued his intentions, but I think it would have been better to just let the father drink. The irony of the whole ordeal just highlights how truly messed up the situation is.