If you are thinking of the fisherman on the Sea Spray in the 1881 census, sorry, but that's a different Thomas Brew [married Jane Seddons]. If you are mixing up the two families that could be your problem. From what you have written this looks more likely to be your Thomas in the 1881 census:
Name Relation Marital Status Gender Age Birthplace Occupation Disability
Thos BREW Head M Male 33 Andreas, Isle of Man, England Farm Serv
Elizabeth BREW Wife M Female 29 Jurby, Isle of Man, England Farm Laborer
Jane S BREW Daur Female 7 m Ballaugh, Isle of Man, England

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Source Information:
Dwelling Bishops Court
Census Place Ballaugh, Isle of Man, Isle of Man
Family History Library Film 1342345
Public Records Office Reference RG11
Piece / Folio 5598 / 76
Page Number 9

He appears to be the son of Wm Brew & Cath Caine bapt 9 May 1847 in Andreas. You can see the siblings under a parent search for those two names on familysearch.com

Have you checked the filmed copy of the marriage register? [1875] It saves a lot of guessing to look at this first where you should find both fathers’ names, occupations, addresses, and the occupations and addresses of the bride and groom.

Sue