Searching for Hillgroves

Hello!  Another American trying to research my origins ...

My 3G-GF was Hugh Luke Hillgrove, born about 1810.  I know his kids were born in County Cork from their death certificates and their kids' birth certificates, so I'm making the assumption that the whole family was in Cork too. 

The Tithe Applotment Book 1823-1837 shows one Hillgrove family in Cork - in Mogeely Parish, Shanakill Townland - in 1830. 

Griffith's Valuation 1847-1864 shows two Hillgroves:  1) Robert in Kinnatalloon barony, Mogeely parish, Shanakill Up. townland leasing from Henry Peard, Esq and to Hugh Cleary. 2) William is in Imokilly, Youghal, Youghal-lands.

I know the family emigrated in the mid-to-late 1840's (Census records say 1846 and 1849),  Not sure if they came over all at once or in separate trips.

Hugh Luke Hillgrove, born about 1810, no info on parents

Married to Catherine Carroll, born June 1804 (from headstone).  Parents are Thomas and Johana (from death certificate)

Children:

Bartholomew Carroll Hillgrove born about 1834

Catherine Hillgrove born about 1840

Thomas F Hillgrove born about 1842

John Carroll Hillgrove born about 1844

Any info would be greatly appreciated.  Cheers.

Paul Brannigan