Translation
(8) Prayer (Kitab Al-Salat): Detailed Injunctions about Witr
كتاب الوتر
(509) Chapter: Regarding Supplication (Ad-Du'a)
(23) باب الدُّعَاءِ
Sunan Abi Dawud 1498 

Narrated Umar ibn al-Khattab:

I sought permission of the Prophet (ﷺ) to perform umrah. He gave me permission and said: My younger brother, do not forget me in your supplication.

He (Umar) said: He told me a word that pleased me so much so that I would not have been pleased if I were given the whole world.

The narrator Shu'bah said: I then met Asim at Medina. He narrated to me this tradition and reported the wordings: "My younger brother, share me in your supplication."

حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا شُعْبَةُ، عَنْ عَاصِمِ بْنِ عُبَيْدِ اللَّهِ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، عَنْ أَبِيهِ، عَنْ عُمَرَ، - رضى الله عنه - قَالَ اسْتَأْذَنْتُ النَّبِيَّ صلى الله عليه وسلم فِي الْعُمْرَةِ فَأَذِنَ لِي وَقَالَ ‏"‏ لاَ تَنْسَنَا يَا أُخَىَّ مِنْ دُعَائِكَ ‏"‏ ‏.‏ فَقَالَ كَلِمَةً مَا يَسُرُّنِي أَنَّ لِي بِهَا الدُّنْيَا قَالَ شُعْبَةُ ثُمَّ لَقِيتُ عَاصِمًا بَعْدُ بِالْمَدِينَةِ فَحَدَّثَنِيهِ وَقَالَ ‏"‏ أَشْرِكْنَا يَا أُخَىَّ فِي دُعَائِكَ ‏"‏ ‏.‏
Grade :  Da'if (Al-Albani) ضعيف  (الألباني)حكم :
Reference : Sunan Abi Dawud 1498
In-book reference : Book 8, Hadith 83
English translation : Book 8, Hadith 1493