Re James and William Brereton / Brierton / Bryarton mid-1800s from Ireland. As you know, first names were usually passed from generation to generation - but this often adds to confusion with research as cousins often shared the same name. That's why Irish families always say "our" Jim or "your" Jim and so on!
Anyway, you may be interested to know that the graves I mentioned in Wicklow with Thomas BRYARTON 1740-1804 include James BIERTON died 1902 aged 75, his son William aged 24, also died 1902, another James Brierton died 1936 aged 56 and 3 other family members.
Another grave is for William Brierton died 1876 aged 53 plus his wife died 1892 aged 84 and their 3 unnamed infants and a son died 1924 aged 68.
In Killoughter cemetery,graves include a William Brereton died 1794 aged 31.
I have names and transcripts for the other family graves as well.