Little is known about her until she was employed by Lady Elizabeth "Betty" and Sir William Fownes at the Woodstock Estate near Inistioge, County Kilkenny, Ireland.

[3] When Eleanor Butler, ran away from home, she was hidden in Sarah's room and Mary smuggled in food for her stowaway.

She was said to have "masculine qualities" and Lady Eleanor's diary records how she would give as good as she got as she bargained loudly with the fishermen, the butchers and the inebriated.

[1] The memorial monument to Mary Carryl, Eleanor Butler and Sarah Ponsonby in the churchyard of St. Collen's Church was erected in 1810.

The inscription on Mary Carryl's part of the monument reads: "In Memory of/ Mrs Mary Carryl/ Deceased 22 November 1809/ This monument is erected by Eleanor Butler,/ and Sarah Ponsonby, of Plasnewydd in this Parish./ Released from Earth and all its transient woes,/ She whose remains beneath this stone repose,/ Stedfast in Faith resigned her parting breath,/ Looked up with Christian joy, and smiled in Death!/ Patient, Industrious, Faithful, Generous, Kind,/ Her Conduct left the proudest far behind,/ Her Virtues dignified her humble birth,/ And raised her mind above this sordid earth,/ Attachment (Sacred bond of grateful breasts)/ Extinguished but with life, this Tomb attests,/ Reared by Two Friends who will her loss bemoan,/ 'Till with Her Ashes...Here shall rest, Their own."