Yes it is the same Isaac Pattemore and I guess you must be related as Pattemore is not a very common name unless you just happen to live in Merriott, Somerset!
I am a decendent of Isaac's daughter Eliza (My 2 x Great grandmother) b. 1845, Merriott who married James Morris at Crewkerne, Somerset, Dec. 15, 1864. They eventually settled in Killamarsh, North Derbyshire via Stafford, South Wales, Taunton? andMosterton. They had six girls, Mary Ann, Hannah J., Rosina, Ada (My Great-grandmother), Louise and Alice.
I have following names for Isaac's children: Robert b. ?, Jane b. 1840, Eliza b. 1845, Emma b. 1847, Hannah b. 1849, Henry b. 1851, George b. 1853, Robert b. 1856 and Alice b.1849. I was given this info by Pat Edwards from Australia and I suspect that it was extracted from census returns. I have not had the opportunity to verify that the details are correct. The info is somewhat suspect as the first Robert seems to have survived and had issue, so why also name a sibling Robert.
As far as Isaac's siblings are conceared I only have William b. 1813. His parents I have as Matthew Pattemore and Ann Osborne, m.Jun.1, 1812. Ann d. 1817. Do you know if this info is correct?If Ann died n 1817 then other children you mention must have been born of a second wife to Matthew.
I have Matthew's parents as William Pattemore b. 1731 and Elizabeth Stone, mar. Oct. 18, 1755. I don't have any siblings for Matthew.
I have William's parents as John Pattemore b. Mar. 4, 1727 and Ann England 1752? Siblings for William I have as Robert d. 1753, Thomas b.1755, Joseph b. 1757, Samuel b. 1761, Samuel b. 1762, Ann b. 1766, John b. 1768 and Ruth b. 1771.
I have John's parents as John Pattemore b. Sep. 1692 and Joan Patten. Siblings I have for John jnr. as Joan b. 1733, Robert chr. Jun. 27, 1736, Aaron chr. Dec. 27, 1749.
I have John (snr.) parents as Aaron Pattemore d. 1727 and Mary d. 1728. Siblings for John I have as Mary b. Jul. 16, 1689, Michael b. Apr. 18, 1696, Sarah b. Feb. 4, 1698, Jane b. Feb. 5, 1791 (but this cannot be right year), Tamzin b. Feb. 2, 1702, John b. Mar. 4, 1703 and Tamzin b. Mar. 21, 1706.
All the above names and dated has come from the sourse I mentioned earlier so If you could confirm any of the above information or add to it I would be most greatful. The only way that I could return the favour is if you have any interests in the Sheffield area of England. I live in Rotherham and often call in at the Sheffield archives if it is of any use to you.