Sunan Ibn Majah 2068
It was narrated that 'Abdullah said:
"We were in the mosque one Friday night when a man said: 'If a man finds a man with his wife and kills him, will you kill him, and if he speaks,will you flog him. By Allah I will mention that to the Prophet (ﷺ). So he mentioned that to the Prophet (ﷺ), and Allah revealed the Verses of Li'an. Then after that the man came and accused his wife, so the Prophet (ﷺ) told them to go through the procedure of  Li'an and he said: 'Perhaps she will give birth to a black child.’ Then she gave birth to a black child with curly hair."
حَدَّثَنَا أَبُو بَكْرِ بْنُ خَلاَّدٍ الْبَاهِلِيُّ، وَإِسْحَاقُ بْنُ إِبْرَاهِيمَ بْنِ حَبِيبٍ، قَالاَ حَدَّثَنَا عَبْدَةُ بْنُ سُلَيْمَانَ، عَنِ الأَعْمَشِ، عَنْ إِبْرَاهِيمَ، عَنْ عَلْقَمَةَ، عَنْ عَبْدِ اللَّهِ، قَالَ كُنَّا فِي الْمَسْجِدِ لَيْلَةَ الْجُمُعَةِ ‏.‏ فَقَالَ رَجُلٌ لَوْ أَنَّ رَجُلاً وَجَدَ مَعَ امْرَأَتِهِ رَجُلاً فَقَتَلَهُ قَتَلْتُمُوهُ وَإِنْ تَكَلَّمَ جَلَدْتُمُوهُ وَاللَّهِ لأَذْكُرَنَّ ذَلِكَ لِلنَّبِيِّ ـ صلى الله عليه وسلم ـ ‏.‏ فَذَكَرَهُ لِلنَّبِيِّ ـ صلى الله عليه وسلم ـ فَأَنْزَلَ اللَّهُ آيَاتِ اللِّعَانِ ‏.‏ ثُمَّ جَاءَ الرَّجُلُ بَعْدَ ذَلِكَ يَقْذِفُ امْرَأَتَهُ فَلاَعَنَ النَّبِيُّ ـ صلى الله عليه وسلم ـ بَيْنَهُمَا وَقَالَ ‏
"‏ عَسَى أَنْ تَجِيءَ بِهِ أَسْوَدَ ‏"‏ ‏.‏ فَجَاءَتْ بِهِ أَسْوَدَ جَعْدًا ‏.‏