What is that which Messenger of Allah ﷺ said to you secretly and you wept and then said to you something secretly and you laughed? Thereupon she said: He informed me secretly of his death and so I wept. He then again informed me secretly that I would be the first amongst the members of his family to follow him and so I laughed. (Using translation from Muslim 2450a)
أَنَّ رَسُولَ اللهِ ﷺ دَعَا فَاطِمَةَ ابْنَتَهُ فَسَارَّهَا فَبَكَتْ ثُمَّ سَارَّهَا فَضَحِكَتْ فَقَالَتْ عَائِشَةُ فَقُلْتُ لِفَاطِمَةَ مَا هَذَا الَّذِي سَارَّكِ بِهِ رَسُولُ اللهِ ﷺ فَبَكَيْتِ ثُمَّ سَارَّكِ فَضَحِكْتِ؟ قَالَتْ سَارَّنِي فَأَخْبَرَنِي بِمَوْتِهِ فَبَكَيْتُ ثُمَّ سَارَّنِي فَأَخْبَرَنِي أَنِّي أَوَّلُ مَنْ أَتْبَعُهُ مِنْ أَهْلِهِ فَضَحِكْتُ