Arthur John O'Leary parents/siblings?

I have an ancestor Arthur John O'Leary who emigrated from Cork to New Zeland in the 1890s as far as I can establish. I have found probable parents, Augustine ? O'Leary married to Margaret Hassett in Cork [1869], and baptisms for Arthur and a sister Margaret Mary [1870 & 1871 respectively]. If this is the family of our Arthur who went to NZ [?] I am having trouble finding anything about the family who remained in Ireland after Arthur departed - deaths, marriage etc. From what I have I think they resided on Blarney Road at the time of the baptisms, but how long for, or what they did etc is of interest. Can anyone assist filling in a few gaps here?