It was narrated from Ibn 'Abbas that:

a woman vowed to perform Hajj but she died. Her brother came to the Prophet (ﷺ) and asked him about that, he said: 'Do you think that if your sister owed a debt you would pay it off?' He said: 'Yes.' He said: 'Then fulfill the right of Allah, for He is more deserving that His rights should be fulfilled.'''

أَخْبَرَنَا مُحَمَّدُ بْنُ بَشَّارٍ، قَالَ حَدَّثَنَا مُحَمَّدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي بِشْرٍ، قَالَ سَمِعْتُ سَعِيدَ بْنَ جُبَيْرٍ، يُحَدِّثُ عَنِ ابْنِ عَبَّاسٍ، أَنَّ امْرَأَةً، نَذَرَتْ أَنْ تَحُجَّ، فَمَاتَتْ فَأَتَى أَخُوهَا النَّبِيَّ صلى الله عليه وسلم فَسَأَلَهُ عَنْ ذَلِكَ فَقَالَ ‏"‏ أَرَأَيْتَ لَوْ كَانَ عَلَى أُخْتِكَ دَيْنٌ أَكُنْتَ قَاضِيَهُ ‏"‏ ‏.‏ قَالَ نَعَمْ ‏.‏ قَالَ ‏"‏ فَاقْضُوا اللَّهَ فَهُوَ أَحَقُّ بِالْوَفَاءِ ‏"‏ ‏.‏