Abdullah bin Ubayd al-Ansari (may Allah have mercy on him) said: I wrote to a brother of mine from Banu Zurayq: What was the ruling of the Messenger of Allah (peace and blessings be upon him) concerning the son of a woman who underwent li'an? He replied: The Messenger of Allah (peace and blessings be upon him) ruled in favour of his mother, and said: "She is in the position of his father and his mother."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الفرائض / 12501