The Prophet [SAW] lay down on a leather mat and sweated. Umm Sulaim got up and collected his sweat and put it in a bottle. The Prophet [SAW] saw her and said: "What are you doing O Umm Sulaim?" She said: "I am putting your sweat in my perfume." And the Prophet [SAW] smiled. (Using translation from Nasāʾī 5371)  

أَنَّ النَّبِيَّ ﷺ اضْطَجَعَ عَلَى نِطَعٍ فَعَرِقَ فَقَامَتْ أُمُّ سُلَيْمٍ إِلَى عَرَقِهِ فَنَشَّفَتْهُ فَجَعَلْتُهُ فِي قَارُورَةٍ فَرَآهَا النَّبِيُّ ﷺ فَقَالَ «مَا هَذَا الَّذِي تَصْنَعِينَ يَا أُمَّ سُلَيْمٍ؟» قَالَتْ أَجْعَلُ عَرَقَكَ فِي طِيبِي فَضَحِكَ رَسُولُ اللهِ ﷺ