Hi Ken
I've just had a quick look at your query and wonder if you have already found these baptisms on the ChurchRecords/Irishgenalogy/ website.
05/01/1853 St Nicholas Parish, Dublin, Bridgit Martin, f John Martin, m Mary King, sps Miche Brien & Mary Kavanagh
14/09/1855 St Catherine Parish, Dublin, Michael Martin, f John Martin, m Mary King, sps Bridget O Donnell
23/06/1857 St Catherine Parish, Dublin, Joannes Martin of 5 Nipoli, dob 20/06/1857, f Joannes Martin, m Maria King, sps Joannes Brennan, Kate Brennan
23/10/1860 St Catherine Parish, Dublin, Patritius Martin of 14 Cole Alley, dob 22/10/1860, f Joannis Martin, m Mariae King, sps Maria Broderick
28/11/1862 St Catherine Parish, Dublin, Mary Anne Martin of 3 Tripolo, f John Martin, m Mary King sps Mary Grattan
26/01/1866 St Catherine Parish, Dublin, Brigida Martin of 7 Tripoli, dob 23/01/1866, f Joannis Martin, m Mariae King, sps Patricius Hickey, Ellena Hickey
I haven't looked for anything else yet, but perhaps you could clarify first if you already have the above details and/or marriage details for John and Mary, or if you are specifically interested in their time in Kildare.
Regards
Linda
Kildare Town Parish Liaison