One possible version：
Dear Johnson,
I received your letter. Now let me tell you the story “The man of Chi worried that the sky might fall down.”.
In the spring and autumn period ，in the state of Qi，there was a man who always let his imagination run away with him。One day he even worried aht the sky would fall on his head ，in which case ，he would have no place available in the morning and at night。He was so worried that neither could he eat nor sleep。After a friend of hiim persuaded him that his fears were groundless ，he relieved himself and so did hid friend。
In my opinion ，it has the similar meaning with the proverb：don’t trouble till trouble troubles you！
Later generations often use this idiom to criticize those who worry unnecessarily。
Yours sincerely
L i Hua
略