Hello Richard,
I tipped off Penn earlier that had replied to the thread.
I am not in anyway related to Penn, I've just been helping her with her research.
We strongly suspect that your Lemon Lemon is the brother of her Leah Lemon. There are a couple of things to support this theory.
1. He was living with Leah's sister, Kate Alexander, in 1901.
2. Both Lemon and Leah gave the name Solomon to sons born in about 1870.
We are looking for proof that Lemon Lemon is the son of Ephrain Zalman Lemon who died in Mile End (London) in 1870.
Do you have the marriage certificate for Lemon Lemon and Mary Cohen from 1851?
I looked through some of the 19th century Jewish records (New Synagogue) and found a couple of things which will interest you.
Mary Cohen was born on 10 July 1831 in Petticoat Lane, Spitalfields. Her Hebrew name was Merle.
She was the daughter of Moses Cohen, a general dealer born in London in 1809. Moses (in Hebrew: Moshe ben Shlomeh ha-Cohn) married Hannah ? (Hebrew name: Hana bat Issachar Ber) on 25 August 1830. She was born in 1807. The marriage records appear to be only in Hebrew so I can't give you her English surname - yet.
I think it is likely that Moses was the son of Shlomeh ben Naftali Hirts ha-Cohn who had married Gittela bat Mordechai in 1803 (New Synagogue marriage register).
Mary was with her parents in the 1851 census at 2 Broadway, Goulston St. Spitalfields. (HO 107/1545 259).
I currently believe that the name Lemon is an anglicisation of the Yiddish name Leyme or Leyman which is generally regarded as an alias/nickname for Hebrew name Yehuda.
If you didn't know ben = son of, and bat = daughter of.
Justin