Catherine and Bridget Brennan

Came to America via Canada specifically to New Jersey sometime in the 1880's from Sligo. They left behind in Sligo a sister Mary Ann who remained on the Brennan Farm. Catherine married William McDonald, they are my great grandparents. Bridget married a man last name Curtis and a 2nd husband last name Sullivan. Apparently, when Mary Ann Brennan passed sometime in the 1930's the farm fell into disrepair. Sometime after the County allowed the sale of the Brennan Farm with little documentation that there were no surviving relatives in America. This is all the information I have of the family left in Ireland. Would be thrilled to know more of the area and possible existing family still in Sligo.