Reagan,

You'll need to do more research in US records to find Catherine O'Leary's date of birth as well as the dates of birth of Molly and Daniel O'Leary. You need the dates of birth for anyone to make a connection with the family as well as find out where in County Cork they originated.

US civil and church records as well as the US census records will help you obtain that information.

Eilís O'Hara