Hello Shelley,
I would be delighted to help but, sadly, the details for John LEE ex-Parkhurst Prison are very few and far between.
He was, as you probably know, sentenced at the Central Criminal Court where he was tried for robbery at St. John's Wood and therefore it is a possibility, although very tentative, that he was born in Clerkenwell in 1827, the son of Josiah and Martha Lee. The transcript of his trial offers no further leads. One other detail which may help, as a matter of exclusion, is that he was the only John LEE to be transported as an "Exile" to Port Phillip.
Do let me know if you feel there are some avenues to be explored, especially if you have BDM Certificates that may indicate parentage, place of birth etc.
For the moment
Tony