The Companion who was hanged at Tan‘eem and the one who killed his brother in battle
27-1-2015 | IslamWeb
Question:
assalam. which sahabi was hanged at taneem and which sahabi killed his own brother at battle of uhd who and whom
Answer:
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 ‘alayhi wa sallam, is His Slave and Messenger.
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The Companion who was killed in At-Tan‘eem was Khubayb ibn ‘Adiyy Al-Ansaari, and Zayd ibn Ad-Dathinah was killed with him in that incident 
both.
Ath-Thahabi 
wrote: "Khubayb ibn ‘Adiyy ibn ‘Aamir ibn Majda‘ah Al-Ansaari … the martyr. Ibn Sa‘d said about him: He participated in the Battle of Uhud. He was among those whom the Prophet, sallallaahu ‘alayhi wa sallam, sent with the Banu Lihyaan. When they reached Ar-Rajee‘, they turned against them. They attacked them, asked their tribe for help to attack them and killed some of them. They captured Khubayb and Zayd ibn Ad-Dathinah and sold them to the people of Quraysh in Makkah who killed them in retaliation for those whom Muslims killed in Uhud. They crucified them at At-Tan‘eem." [As-Siyar]
As for the Companion who killed his brother in the Battle of Badr, it was Mus‘ab ibn ‘Umayr 
. He killed his brother ‘Ubayd ibn ‘Umayr. Ibn Katheer commented on the verse that reads (what means): {You will not find a people who believe in Allaah and the Last Day having affection for those who oppose Allaah and His Messenger, even if they were their fathers or their sons or their brothers or their kindred. Those – He has decreed within their hearts faith and supported them with spirit from Him. And We will admit them to gardens beneath which rivers flow, wherein they abide eternally. Allaah is pleased with them, and they are pleased with Him – those are the party of Allaah. Unquestionably, the party of Allaah – they are the successful.} [Quran 58:22] He wrote:
"It has been said that the verse {even though they were their fathers} was revealed about Abu ‘Ubaydah when he killed his father during the battle of Badr; and that {or their sons} was revealed about Abu Bakr As-Siddeeq who was about to kill his (disbelieving) son ‘Abdur-Rahman in Badr; and that {or their brothers} was revealed about Mus‘ab ibn ‘Umayr who killed his brother ‘Ubayd ibn ‘Umayr in Badr; and that {or their kindred} was revealed about ‘Umar who killed one of his relatives in Badr; and also Hamzah, ‘Ali and ‘Ubaydah ibn Al-Haarith; they killed their close relatives ‘Utbah, Shaybah and Al-Waleed ibn ‘Utbah that day, and Allaah knows best." [Tafseer Ibn Katheer]
Allaah Knows best.