After their meal, the son led his father to the restroom and helped him wipe the stains off of his clothes. Then, he helped his father comb his hair, put on his jacket, and straighten his glasses.
After they came out, the son paid the bill and started to leave. Everyone watched them in dead silence. No one could understand how someone could embarrass himself in public like that.
Then, all of a sudden, one of the diners at a nearby table called out to the son. "Don't you think you have left something behind?" he asked.
"No, sir, I don't think so," the son replied.
"Yes, you have!" replied the gentleman. "You have left a lesson for every son, and hope for every father."
And with that reply, the entire restaurant fell silent.
Taking care of those who once cared for you is one of the highest honors we have.