Hi everyone - Though I have marked my enquiry as complete I thought I would let you know of an update.
Whilst researching deeper into my tree I located a marriage which I had not found before and the couple had moved to a different county.
Having dug that little bit deeper I found that John Grey's sister was also a nurse travelling to New York - Mary Wilkinson GRAY was found travelling to New York on the SS Santa Teresa via Peru arriving in NY 24th Feb 1921 to work as a nurse for a Mr HOLLOWAY - she was recorded as going to join her cousin Margaret WOOD at 136 East 60th Street.
The odd thing about the above ship's manifest was Margaret WOOD arrived in NY 28 February and on her entry she recorded joining her cousin John GRAY at the same address so a mystery as to why Mary would record joining with Margaret as she was not yet there and her brother seemingly was.
The address 136, East 60th Street is as someone suggested an agency address.
I now need to find John's landing - I now know John to have been born in Sunderland, Durham, England (My hometown) in 1869 and was last registered as a Draper's Assistant in the UK in the 1891 census.
Many thanks again and I hope everyone is staying safe. - Best regards - Bryn