Well, whether it has anything or nothing to do with my own family, that was fun..
Meath Heritage: *Baptism of Joseph Downes in the parish of Monalvey Kiltale on 20 May 1847. Parents Christopher & Margaret (Mooney), sponsors Owen Delaney & Mary Mooney.
I've found 6 siblings - 2 Marys and 2 Patricks (earlier infants presumably died), Rose and Christopher.
Found in Dod’s Peerage: Sir Joseph Downes, son of Christopher Downes, farmer of Kiltale, Trim, co. Meath, and Margaret, dau. of Patrick Mooney of Trim; born 1848*; married (1) 1884 Teresa (d.1904) dau. of Dennis Carton of Dublin (2) 1909 Joanna, dau. of Thomas Davy of Newtown, Tipperary and widow of Ald. James Hennessy of Palmerston Road, Dublin; ed. at Kiltale and Trim; is in business as a merchant baker and confectioner in Dublin; JP Dublin, Sherriff 1900. Residence: South Hill, Milltown, co. Dublin.