Trying to find Great Great Grandfather

[LisaW1970]

Hi, how would I find my GG Grandfather, the only information we have is this:

Name - Frederick Wilson rough guess at area Birkenhead Cheshire or Liverpool.

First named on a baptism record of our great grandfather, William Knight Gordon Wilson, as follows:
William Knight Gordon Wilson baptised 7/10/1891 at St James Church Birkenhead Cheshire, mum Jemima Wilson and dad Frederick Wilson - seaman.

No link between Jemima and Frederick snr can be found apart from this entry.

Second reference Frederick Knight Gordon Wilson marriage certificate 1912 as follows:
Dad - Frederick Wilson master mariner.

I've found a few merchant service records /grade certificates of a Frederick (William) Wilson as follows:
28/1/1891 second mate
21/4/1894 first mate
30/12/1897 Master of foreign going ship

How would we find out the personal details for this person from his merchant certificates?  We aren't sure if this is our chap but certificates were granted in Liverpool and "son" lived in Birkenhead.  And last grade of master ties in with occupation on sons marriage certificate.  It's a long shot but we are really stumped!

Should mention Frederick Knight Gordon Wilson was adopted by Sarah and George Knight between 1891 and 1901. So can't find any link between father and son other than what I've already mentioned.
Any help greatly appreciated 👍

[Spelk]

The baptism record is not for William Knight Gordon WILSON but for Frederick Knight Gordon WILSON. Had me chasing up wrong records form a while.
Have you traced his birth certificate? That might give truer information such as maybe Jemima was not married and lied at the baptism - like my G Gmam did.

[LisaW1970]

Yes, I accidentally put William instead of Frederick, thanks for pointing this out!

[LisaW1970]

Hi, unable to verify birth.  Have a theory that he was born in workhouse to Minnie Roberts no maiden name provided when registered at birth in the workhouse.  He is the baptised Frederick knight Gordon Wilson, a few weeks later, adopted by the knight family.  Jemima then changes name to Mina and marries a Knight not from same knight family as Fred is adopted into.  We have no idea where the Frederick Wilson came from! It's been a nightmare! But don't if or how we can prove any of it, or if Frederick Wilson was real

[heywood]

  Hello and welcome.

Do you have records for Jemima?

[LisaW1970]

Thank you! You might regret that welcome!
We have no confirmed identity for Jemima.

We think she has gone by various names
Jemima Roberts, Minnie Roberts and Mina Roberts later Mina Knight.

Only once identified as Jemima Wilson. Can't find her anywhere else this variation.

Can't find birth record for Frederick Wilson but found record for Frederick Roberts, mum Minnie Roberts, dad Frederick Roberts mum maiden name unknown. 

[heywood]

With him being baptised as Knight, is Jemima connected to the Knight family?

[heywood]

There is this marriage - 1900, Belfast but nothing to say he is your man
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1900/10351/5768158.pdf

[Spelk]

Heywood, that link takes me to a site for searching Irish records - but what then am I supposed to search for? Why not just say what you found?