Sussex in general / more specifically Brighton and Hastings

[sillgen]

Have you tried the non conformist records?
Have you dismissed the William Henry Graham baptised in Chichester on 18th March 1816?    Son of William and Susan.  Father was a soldier at the Barracks there.   Might be worth tracing him forwards to see if he turns up so you can eliminate him.  Not with father George but worth a look?

[Tom Huygens]

Have you tried the non conformist records?
Have you dismissed the William Henry Graham baptised in Chichester on 18th March 1816?    Son of William and Susan.  Father was a soldier at the Barracks there.   Might be worth tracing him forwards to see if he turns up so you can eliminate him.  Not with father George but worth a look?

Yes, we did dismiss him because neither the birth date, not the birth place, nor the name of the father are correct. But I might give him another look... You never know.

[Tom Huygens]

The only thing I was able to find, but it's a stretch, is a William Brayham in Hastings in 1851.
He has the right age and is also a carpenter, but there is that one letter and the fact that this one was born in Kent and not Brighton.

For those who might be interested: in the meantime, through DNA, I found out that I'm related to several people who all descend from a certain Bertram George Adams. He was the illegitimate son of Clara Adams.

He was born in 1852, only 3 months after my William Graham left Hastings. His mother Clara lived in the same street as the aforementioned William Brayham...

Chances are that "William Brayham" is indeed one and the same person as my William Graham, making a girl pregnant and leaving her to get married elsewhere.