O Allah, Your male slave and the child of Your female slave is in need of Your mercy, and You are no...
Reference:Al-Hakim 1/359 who graded it authentic and Ath-Thahabi agreed with him. See also Al-Albani, Ahkamul-Jana'iz, p. 125.Hisnul Muslim 159
اللهُـمِّ عَبْـدُكَ وَابْنُ أَمَـتِك احْتـاجَ إِلى رَحْمَـتِك وَأَنْتَ غَنِـيٌّ عَنْ عَذابِـه إِنْ كانَ مُحْـسِناً فَزِدْ في حَسَـناتِه وَإِنْ كانَ مُسـيئاً فَتَـجاوَزْ عَنْـه
Allāhumma `abduka wabnu 'amatikiḥtāja ilā raḥmatik. wa anta ghaniyyun `an `adhābih. in kāna muḥsinan fazid fī ḥasanātih. wa in kāna musī'an fatajāwaz `anh.
O Allah, Your male slave and the child of Your female slave is in need of Your mercy, and You are not in need of his torment. If he was pious then increase his rewards and if he was a transgressor then pardon him.