Irwins from Ireland

[Dennis Lord]

Hi All,

I am tracing my roots. My gggrandfather is Samuel Irwin born May 13th, 1828 who emigrated to Canada in 1847 according to canadian census'.
I cannot find a port of entry in Canada with his name, however I did see his name on the New York port of entry.
Samuel was on the ship United Kingdom and arrived in New York on July 14th, 1846. The manifest says he was 19yrs. It seems he arrived with two other (brothers, cousins?). Thomas who was 23, and Robert who was 17.
The port of departure is listed as Liverpool.
I still have not been able to find out if this is my Samuel Irwin or not, and where the other two boys went, if Samuel came to Canada on his own.
In canadian census' the enumerators write he is irish and from Ireland.

Is anyone able to help me find out if these three guys are related and where they came from and who the parents are? I understand many records were burnt in Ireland.

Thanks in advance,
Dennis