Could this be Mary Ellen's birth? Mary Collins, mother McManus, born Liverpool, 1866, March quarter, Vol 8b, page 54.
On the other hand the 1871 census (from a transcription) lists Dennis, 40, born Ireland; Margaret, 32, born Greenock; Eliza S, 10, born Ireland; Mary E, 4, born Mauritius.
Is Denis the 22-year-old private in the 95th Regiment, born Cork, Dunaway in the 1851 census in Portsea, Hampshire?