Sayyidah Aishah (may Allah be pleased with her) said: Sayyiduna Abu Bakr (may Allah be pleased with him) died on the night of Tuesday, with eight nights remaining of Jumada al-Akhirah, in the year 13 AH. He left instructions that he be washed by Sayyidah Asma' bint Umays (may Allah be pleased with her), who was his wife; she had become weak, so Sayyiduna Abd al-Rahman bin Abi Bakr (may Allah be pleased with him) assisted her.
This connected (mawsul) hadith, its narrator being Muhammad bin Umar al-Waqidi, the author of the history and the Maghazi, is not strong. It has supporting mursal reports from Ibn Abi Mulaykah, and from Ata bin Abi Rabah from Sa'd bin Ibrahim, that Asma' bint Umays washed her husband Abu Bakr (may Allah be pleased with him), and some of them mentioned that Abu Bakr (may Allah be pleased with him) had instructed that.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6663
Sayyidah Aishah (may Allah be pleased with her) said: I heard the Messenger of Allah (peace and blessings be upon him) saying: "May Allah Almighty have mercy on a man who is washed by his wife and shrouded in his old clothes." She said: That was done with Abu Bakr (may Allah be pleased with him); his wife Asma' bint Umays (may Allah be pleased with her) washed him, and he was shrouded in the clothes he had worn out.
This chain is weak.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6664
It is narrated from Sayyidah Aishah (may Allah be pleased with her) that she said: Had I known beforehand what I came to know afterwards, none but his (peace and blessings be upon him) wives would have washed him (peace and blessings be upon him).
The Shaykh said: She expressed regret over that, and one only regrets something that is permissible.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6665