Khadija’s Merits And Her Death (رضي الله عنها)
Narrated Abu Huraira (رضي الله عنه):
“Jibreel came to the Prophet (ﷺ) and said, “O Allah’s Messenger (ﷺ)! This is Khadija coming to you with a dish having meat soup (or some food or drink). When she reaches you, greet her on behalf of her Lord (i.e. Allah) and on my behalf, and give her the glad tidings of having a Qasab palace in Paradise wherein there will be neither any noise nor any fatigue (trouble).” 
Narrated Isma’il (رضي الله عنه):
“I asked ‘Abdullah bin Abi Aufa, “Did the Prophet (ﷺ) give glad tidings to Khadija?” He said, “Yes, of a palace of Qasab (in Paradise) where there will be neither any noise nor any fatigue.”” 
‘Aisha (رضى الله عنها) reported:
“Never did I feel jealous of any woman as I was jealous of Khadija (رضى الله عنها). She had died three years before he (the Holy Prophet) married me . I often heard him praise her, and his lord, the Exalted and Glorious, had commanded him to give her the glad tidings of a palace of jewels in Paradise: and whenever he slaughtered a sheep he presented (its meat) to her female companions. 
Narrated Aisha (رضى الله عنها):
“I did not feel jealous of any of the wives of the Prophet (ﷺ) as much as I did of Khadija though I did not see her, but the Prophet (ﷺ) used to mention her very often, and whenever he slaughtered a sheep, he would cut its parts and send them to the women friends of Khadija.
When I sometimes said to him, “(You treat Khadija in such a way) as if there is no woman on earth except Khadija,” he would say, “Khadija was such-and-such, and from her I had children.”” 
Narrated ‘Aisha (رضي الله عنها):
“Once Hala bint Khuwailid (رضى الله عنها), Khadija’s sister, asked the permission of the Prophet (ﷺ) to enter. On that, the Prophet remembered the way Khadija used to ask permission and that made him sad.
He said, “O Allah! Hala!” So I became jealous and said, “What makes you remember an old woman amongst the old women of Quraysh, an old woman (with a teethless mouth) of red gums who died long ago, and in whose place Allah has given you somebody better than her?”” 
‘Aisha (رضى الله عنها) narrated that she said:
“When Allah’s Messenger (ﷺ) remembered Khadija (رضى الله عنها), he was praising her a lot. She said: I felt jealous and said: How often you used to remember that who is with red gums (i.e. an old woman)! Allah has given you a better one in her instead.
Allah’s Messenger (ﷺ) said: “Allah has not given me a better one in her place; she believed in me when everyone disbelieved in me, knew that what I have brought is the truth when all the people did not, gave me her money when the people obstructed me, Allah, the Almighty, granted me children from her and deprived me children from my other wives”” 
Ummul-Mumineen Khadija bint Khuwailid died soon after Abu Talib, but the exact time difference between the two deaths is not known. 
Ummul-Mumineen ‘Aisha loved the Prophet Muhammad (ﷺ) so-much-so that she felt jealous of Khadija even though Khadija was not physically present as a co-wife, rather Khadija held a higher place in the Prophet’s blessed heart- and this made our mother ‘Aisha envious.
 Sahih Al-Bukhari 3820.
 Sahih Al-Bukhari 3819.
 This refers to ‘Aisha’s consummation when she was 9.
 Sahih Muslim 2435.
 Sahih Al-Bukhari 3818.
 Sahih Al-Bukhari 3821.
 Musnad Ahmad 24864. Graded as Sahih by Shaikh Shuaib Al-Arnauut. (Translation from- qurananswers.me/2018/11/13/aishas-jealousy-of-khadija-bint-khuwaylid/)
 Dr.Mahdi wrote: It is also said that it (Khadija’s death) happened in the month of Ramadan in the tenth year after the Prophet’s commissioning and three years before Hijirah. This seems to be the most reliable version.-See the earlier discussion (Abu Talib’s Death).. Also see Dr.Qalaji: Footnotes of Dala’il An-Nubuwwah by Al-Baihaqi (2/353) were he mentioned most of the opinions in this regard. (Vol.1, p.251)
Excerpt taken from the Book ‘The Biography of Prophet Mohammad (ﷺ)’ Vol 1 by Mohammad Thajammul Hussain Manna