(Ed - One reason I found this story so interesting is that, hey, even Enlightened Ones sometimes have problems with their parents)
Sariputta was the Buddha's top disciple. His wisdom and ability to teach was said to be second only to the Buddha.
Sariputta died before the Buddha. A few months before his death, he bade his last farewell to the Buddha (all Enlightened Ones know when they're dying) and told him that he wanted to go home to repay his mother's kindness. The Buddha answered, "I understand".
Sariputta's mother was Sari. (The word Sariputta means "Sari's son"). She was very upset that her son became a monk. She much rather that he lived a lay life. So after he entered monkhood, she refused to talk to him.
When Sari heard that her son was returning, she was overjoyed. But when she saw him and realized that he was still a monk, she refused to see him or talk to him.
As days went by, Sariputta became weaker and weaker. Still, his mother refused to talk to him.
It was said that on the night before Sariputta's Final Nirvana (ie death), gods came to his room by the truckloads to pay their final respect. According to the scriptures, Sariputta was not only a famous teacher of men, he was also a teacher of gods. All these gods come to say goodbye to their teacher.
It was said that the glorious lumination of the gods brightened up the whole room. Sari was awoken by the bright light and came to see what the commotion was. When she witness all these gods paying respects to her son (instead of the other way round!), she realized that her son was no ordinary monk after all. Only then did she talk to him.
Sariputta's last act before his death was to teach his mother the Four Noble Truths. Learning thus, mum became a Stream- Winner. Sariputta had thus repayed his mother's kindness and he passed away.