Sunan Ibn Majah, Volume 3, Book 9, Hadith 1969 (DarusSalam) ⓘ
It was narrated from Abu Hurairah: that the Messenger of Allah said: "Whoever has two wives and favors one of them over the other, he will come on the Day of Resurrection with one of his sides leaning."
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا وَكِيعٌ، عَنْ هَمَّامٍ، عَنْ قَتَادَةَ، عَنِ النَّضْرِ بْنِ أَنَسٍ، عَنْ بَشِيرِ بْنِ نَهِيكٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " مَنْ كَانَتْ لَهُ امْرَأَتَانِ يَمِيلُ مَعَ إِحْدَاهُمَا عَلَى الأُخْرَى جَاءَ يَوْمَ الْقِيَامَةِ وَأَحَدُ شِقَّيْهِ سَاقِطٌ " .
also referenced under: Hadith 1969 (Reference) & Book 9, Hadith 2045 (In-Book)