The Sunnahs of the Prophet are well-established.
Helping one's family with household chores:
On the authority of Al-Aswad, who said:
I asked 'A'ishah, may Allah be pleased with her,
"What did the Prophet, peace and blessings of Allah be upon him, use to do in his home?"
She said,
"He used to be in the service of his family—
meaning serving them—
and when the time for prayer arrived,
he would go out to the prayer."
Narrated by Al-Bukhari.