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I looked on the subscription site Roots Ireland for Padden baptismal records in Co. Mayo. The Belmullet records have Paddens starting in 1841 and the Kilmore Erris parish records have Paddens starting around 1860. I verified that there were no Padden baptismal records in Belmullet with a mother with surname Heffron.
Here is a link to the 1856 Griffiths Valuation head of household listing for Kilmore civil parish. I see three Thomas Padden records but no Richard records.