Conversation so far:
When was Periyar E. V. Ramasamy born?
17 September 1879
What did Periyar E. V. Ramasamy do as a child?
Periyar attended school for five years after which he joined his father's trade at the age of 12.

Question: What did he do at his father's trade?
Self-contained rewrite: What did Periyar E. V. Ramasamy do at his father's trade?