Muwatta Malik
Setting Free and Wala'
Hadith #15
38.15
وَحَدَّثَنِي مَالِكٌ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ أَعْتَقَ وَلَدَ زِنًا وَأُمَّهُ .
Malik related to me from Nafi that Abdullah ibn Umar freed an illegitimate child and its mother