This is a beautiful and touching real-life story of a hawker in Thailand who, one day, saves a poor young boy.
Thirty years later, the boy has grown up to become a hospital doctor, and as providence would have it, saves the hawker from bankruptcy, when the latter becomes riddled with hospital debts.
Kindness begets kindness. Or, as the bible teaches us in Galatians 6:7 (ESV):
Do not be deceived: God is not mocked, for whatever one sows, that will he also reap.