It was narrated that Ibn 'Abbas said:

Sa'd bin 'Ubadah came to the Prophet and said: "My mother has died and she had a vow to fulfill but she did not do so." He said: "Fulfill it on her behalf."

أَخْبَرَنَا هَارُونُ بْنُ إِسْحَاقَ الْهَمْدَانِيُّ، عَنْ عَبْدَةَ، عَنْ هِشَامٍ، - هُوَ ابْنُ عُرْوَةَ - عَنْ بَكْرِ بْنِ وَائِلٍ، عَنِ الزُّهْرِيِّ، عَنْ عُبَيْدِ اللَّهِ بْنِ عَبْدِ اللَّهِ، عَنِ ابْنِ عَبَّاسٍ، قَالَ جَاءَ سَعْدُ بْنُ عُبَادَةَ إِلَى النَّبِيِّ ﷺ فَقَالَ إِنَّ أُمِّي مَاتَتْ وَعَلَيْهَا نَذْرٌ وَلَمْ تَقْضِهِ قَالَ " اقْضِهِ عَنْهَا ".