Cain family of Dunhill Parish

Hello from Canada!

I married into the Cain family from PEI and was amazed when we went to visit the local parish graveyard to see one of their ancestors, William, came from Dunhill Parish and emigrated to PEI in 1829.  If anyone could assist us in finding any information about him and his family, it would be much appreciated.  Here's what we know from the info on the gravestone:

William Cain b. 1788 was married to Mary Walsh b. 1799

We know they arrived in PEI in 1829 and their son James died in 1847 so he must have just been born as he is listed on his gravestone as a native of Dunhill.  The inscription is:

Erected
by 
William Cain
In memory of his son
James Cain
Who departed this life
March 11th 1747
Aged 18 years
native of the parish
Dunhill County
Waterford Ireland

There were only four ships that came to PEI in 1829: Pandora, Benjamin Shaw, Galbraith and Baldwin.

1. Are there any records that might show what ship they took or when they departed Waterford?  It's probably a long shot, but it can't hurt to ask!

2. Could there be a baptismal document for James' birth in 1829?

3. Could there be a marriage certificate or record of William and Mary's?

4. Most importantly, are there any records at all of William's ancestors?  We'd love to know how far back we can trace this Cain family in Dunhill/Waterford.  He came to PEI to farm, and there are still Cains on that very same land since 1829!  We're guessing he was a farmer himself or a farmhand most likely.

5. Are there any Cains still in Dunhill?

Thanks so much for any assistance,

Malachy Maguire (and Paula Cain)