Bell and Plant Families

My name is Delwyn Bergman and I live in Australia.  I am having trouble finding any information about my Great Great Great Grandmother.  Her name was Jane Bell.  She married Samuel Plant circa 1827 in County Cavan.  Samuel had been born circa 1800.  His parents were Samuel Plant and Mary Dignam. 

I know of 6 children born to Samuel and Jane, but on the death of Samuel it had that there had been 7 children.

We have found the records of Baptism for some of the children in Lurgan (Virginia), but have information that the family lived at Cornsalieve County Cavan.

The children were John born 1831, Mary 1832, James 1834, Samuel 1836, Katherine 1839, Eleanor (Ellen) 1841.

John and James emigrated to Australia in 1856 on the ship "Phoebe Dunbar"

Samuel emigrated to Australia in 1858 on the ship "Alfred"

Samuel born 1800 emigrated to Australia with daughters Katherine and Ellen in 1863 on the ship "Norman Morrison".

We believe that Jane had died before Samuel b1800 emigrated. 

We have also been told that Jane had come from County Meath.  We have also been told that her brother had also emigrated to Australia.  But we have never been able to find confirmation of this.

I am hoping that someone can help.