stillsearching on Family Tree Circles

I am looking for decendents of my great grand father and grandfather. They were from co.Meath in Ireland, (and I think from Oldcastle).

I think my Great grandfather was born on 14th September 1868, later, marrying Margaret Vaughan.
They had a son John Sheridan (my Grandfather) on 9th january 1886. From census records I believe their address at that time to be Boolies ,Oldcastle co. Meath.

The next thing I can find about him is when John Jr. married in 1919 in Melbourne Australia and had a son (my father) baptised Matthew John, but always called 'Tommie'.

Tommies' father/John's wife died 9 months later and is buried in Brighton Cemetery Melbourne.

I can find no further information on John Sheridan. Tommie was reared by his maternal family and I cannot trace his father.

Can someone out there please help me???????????