I too an researching the Hippards. My great grandmother was a Hippard (Agnes) She had brothers called Mark and William but they were born later than the two you're looking for. I believe the brothers you are looking for were the children of George Hippard and Elizabeth Meacham who came originally from Radstock,Somerset. In the 1851 census they had the following children: Jacob(21) Hannah(15) George (12) William (8) Mark (4) and Matthew(1). Jacob married Emily Hilton and they lived in the parish of Llantrisant, South Wales. They are my direct descendants. Let me know if you need more info. I'd be glad to help.