hi there,
i did a couple of free searches on scotlandspeople and here is what i found...
(i did not view actual certs, so can't be certain that these are definitely the family that you are looking for).
there are 2 lewis jack deaths in avoch btwn 1855 & 1881 - i couldnt find lewis sr on census, so only assuming it was before 1881).
1. 1874 aged 72yrs - this is a good possible.
2. 1879 aged 0yrs - obviously this isnt the correct one.
then possible death dates for lewis jr. - 4 matches in avoch btwn 1881 and 1954.
(assuming they stayed in avoch).
1. 1902 < 30 though, so not him as listed as 41 on 1881 census.
2. 1906 < 30 so above also applies.
3. 1908 aged 68. this puts him born c 1840, so possible match, as age matches up with 1881 census age.
4. 1946 aged 95. this puts him born c 1851, still possible match, but the age difference nearly 10 years out.
there is one jane ralph death in Avoch in 1907 aged 66
then substitute ralph for jack, there is also one match for same year and age.
i hope this helps a little.
kind regards,
Lorna.
