Conversation so far:
What was something that happened in 1990?
Leonard won his first cap in a 'friendly' on 28 July 1990.
Were there other winds in 1990?
CANNOTANSWER.
What happened in 1991?
England won back-to-back Grand Slams in 1991.

Question: Did Leonard play an important role in these wins?
Self-contained rewrite: Did Leonard play an important role in England's Grand Slams wins?