Want this question answered?
Umar (omar)
3rd caliph H. Usman ra was son in Law of prophet Muhammad saw .
Perhaps you are referring to abu Bakr? Abu Bakr was one of Muhammad's fathers-in-laws and became the first Caliph.
Caliph
They had ordered Abu Bakr to be a Caliph since he knew Muhammad.
Caliph (or Khalifa in Arabic)
Caliph refers to a Muslim civil and religious ruler, widely viewed as the successor of Muhammad.
Ali son of Abu Talib. Ali was the cousin of Prophet Muhammad and later became his son-in-law. He later became the fourth caliph of Islam.
He was the third Caliph after Muhammad's death, and was killed by the Umayyads.
Caliph.
Caliph Sulaiman
Caliph (or Khalifa in Arabic)