Not only was it COMMON practice amongst Sephardis to name children after
their living grandparents, it was the USUAL practice.
The first child of each sex was named after the paternal grandparent, the
second, of the same sex, after the maternal grandparent.
Names, therefore, are repeated every second generation.
It was also usual to name further children (the third or subsequent child of
each sex) after their living uncles or aunts.
There are exceptions to this rule, myself included.
If this rule had been followed, I'd be Joseph and not Henry!
This can give a clue to the names of unknown grandparents.
Eg. If the firstborn son was called David, then it is probable that his
paternal grandfather was also called David.
Names can also disappear >from families.
In my family there were two Michaels (one the grandson of the other) who
both died young.
It's now considered to be an 'unlucky' name in my family and never used.
The reason the parish records entries stopped in 1837 was that compulsory
civil registration of births was introduced that year.
Every (live) birth was required to be registered so that Parish Record
entries were no longer needed.