Assalamu alaikum.Is there a report that Prophet(peace and blessings of Allah be upon him)used to distribute camel meat on the death anniversary of Khadeejah(Allah be pleased with her)?Is this a Hadees or written in History?Some Muslims are using this report to justify that we can do such acts and is Sunnah when someone dies and since Prophet(peace and blesings of Allah be upon him)was born and died on monday they say they can organize feast and make Mawlid as well and celebrate Prophet's(peace and blessings of Allah be upon him)birthday as death also occured on same day. Is the above report whether Hadees or written in history authentic?Can this report be used to justify above mentioned acts? Thank you.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu 'alyhi wa sallam, is His slave and Messenger.

What you mentioned in the question is neither confirmed in a Prophetic narration nor in the Prophet’s biography.  What is confirmed is that the Prophet would slaughter a sheep and would order that it be sent it to the friends of his wife Khadeejah but it was not mentioned that this was on her anniversary.

Also, it is not correct to conclude from what you mentioned in the question the permissibility of celebrating the birthday of the Prophet . The mentioned acts are evidence that the Prophet used to fast on Mondays of each month of the year as a sign of being grateful and thankful to Allaah, and he did not only do so in the month in which he was born. 

For more details in this regard, please refer to Fatwas 81804 and 83240.

Allaah Knows best.