Anyone Related to the Hilaire OR St Hilaire Family

I have confirmed family tree in NSW. Australia, of my gr/grandfather John Bollingbrooke Hilaire married to Elizabeth Ann Jupp - 17th Nov.1874 in Sydney.John born about:1850 Middlesex England.(no birth found on BDM England)
John's parents were John St Hilaire? and Eliza Fletcher from England?
I have looked at all records and Indexs, but cannot confirm how John Bollingbrooke Hilaire arrived in Australia.
Anyone related or could have any information or suggestions.
I would be very gratefull, also anyone who would like Hilaire family tree I will send.
Regards Ruby