What would a ''spare the rod, spoil the kid'' believer do if even that doesn't work?

Both my husband and I will raise our baby boy differently without hitting him. However, I don't further argue with other people's beliefs on how to raise kids.

Though I would like to know what would someone that believes in spanking (using a belt, wooden spoon, paddle, etc) do if not even that works in the end. This is a real story I'm about to say:

My mother's own cousin (whom is now in his 50's, disabled, on the dialysis and back at home with his mother caring for him) was very troubled as a kid. He joined a gang, skipped school, got into fights, sneak out of his house, etc. His parents did spanked him. He had a high pain threshold and didn't care about getting physically punished. His own words according to my mother were ''So what if my dad gets the belt, I'll still sneak out, I'll find a way''.

By the time he became an adult, his father threw the towel and claimed there was nothing he can do anymore. He was very different from the rest of the siblings. He messed with the wrong people much later on in life and nearly got beaten to death. It was relating to drugs and owning someone money or stealing from them. His father passed away knowing his son never got his life on track, never became better, never stopped stealing nor smoking nor using drugs. His mother (mom's aunt) is devastated about her son's condition, knowing that he'll likely die before she does. That was their first and oldest child.

In that case, what would a pro-spanker do? What would they think if not even physical punishment makes the person better and they are corrupted to the very end? What would be their solution in that case?

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9 mo
So if they actually followed the ''spare the rod, spoil the kid'' and it still didn't work, what else would a pro-spanker do?
What would a ''spare the rod, spoil the kid'' believer do if even that doesn't work?
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