Hadith: The Messenger of Allah (may Allah's peace and blessings be upon him) entered upon us after his daughter had died and said: "Wash her three times, or five times or more if you find that necessary. Wash her with water and Sidr (ground lotus leaves), add camphor (or a pinch of camphor) to water in the last time, and let me know when you finish."

عن أُمّ عَطِيَّةَ الأنصارية رضي الله عنها قالت: «دخل علينا رسول الله صلى الله عليه وسلم حين تُوُفِّيَتْ ابنته، فقال: اغْسِلْنَهَا ثلاثا، أو خمسا، أو أكثر من ذلك -إن رَأَيْتُنَّ ذلك- بماء وَسِدْرٍ، واجْعَلْنَ في الأخيرة كافُورا -أو شيئا من كافور- فإذا فَرَغْتُنَّ فَآذِنَّنِي ». فلما فَرَغْنَا آذَنَّاهُ، فأعطانا حَقْوَهُ، وقال: أَشْعِرْنَهَا بِهِ -تعني إزاره-. وفي رواية «أو سَبْعا»، وقال: « ابْدَأْنَ بِمَيَامِنِهَا ومَواضِعِ الوُضوء منها» وإن أُمّ عَطِيَّةَ قالت: وجعلنا رأسها ثلاثة قُرُون».
[صحيح] - [متفق عليه]

Umm ‘Atiyyah al-Ansāriyyah (may Allah be pleased with her) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) entered upon us after his daughter had died and said: "Wash her three times, or five times or more if you find that necessary. Wash her with water and Sidr (ground lotus leaves), add camphor (or a pinch of camphor) to water in the last time, and let me know when you finish." When we finished, we told him, so he gave us his lower garment and said: "Let it be the first thing you shroud her in." A different narration reads: "or seven times", and he said: "Start with her right side and the organs of ablution." Umm ‘Atiyyah said: "We plaited her hair into three braids."
Sahih/Authentic. - [Al-Bukhari and Muslim]

Explanation

When Zaynab, one of the Prophet's daughters died, the Prophet (may Allah's peace and blessings be upon him) entered upon the women who were washing her, and Umm ‘Atiyyah al-Ansāriyyah was one of them. He wanted to teach them how to wash her, so that she would come out of this world and meet her Lord in a state of cleanness and purity. He ordered them to wash her three or five times, or more if it was necessary. For extra cleanness and a solid corpse, the Prophet (may Allah's peace and blessings be upon him) ordered them to add Sidr (ground lotus leaves) to the water and to add camphor in the last wash. This would solidify the dead body, and with the perfume, insects would stay away from it. Moreover, the Prophet (may Allah's peace and blessings be upon him) advised them to start with her right organs, which are washed in ablution, and asked them to let him know when they finished. They informed him after they were done with washing her, and he gave them his lower garment, which touched his pure body, to be the first thing they wrap her body in. He wanted that to be a blessing for her in her grave. The women who were washing Zaynab undid her hair, washed it, and plaited it into three braids, one at the forehead and two at the sides, and they threw them to her back.