The following answer does not intend to hurt the feelings of our dear brothers and sisters of Ahle Sunna as we are all followers of the same religion.
Ayatollah Sayed Ali Sistani, the great Shia Marja in Iraq, said,
“Shiites should defend Sunnis’ social and political rights before
defending their own rights, and we call [everyone] for unity. As I
have said before, Shiites should not call Sunnis their brethren, but
Unfortunately, the following is early Islamic history:
The situation was hostile from the beginning. After the death of the Holy Prophet his Ahl-ul–Bayt (Ali ibn Abi Talib, his wife Fatima bint Muhammad and their two children Hassan and Hussain) were treated very badly by the authorities who took power, even though the Prophet had demanded his ummah to show love for his family.
- Many historians (e.g. al-Tabari, al-Andalusi, Ibn Abil Hadid, al-Baladri, Sharestani, Ibn Qutaybah) reported about Umar b. al-Khattab’s attempt to burn the house of Fatimah al-Zahrah to force Ali ibn Abi Talib to give allegiance to Abu Bakr.
Those who refrained from giving the bayah (allegiance) to Abu
Bakr were Ali, Abbas (the uncle of the Prophet), Zubayr b. al-Awam
(cousin of the Prophet) and Sa’d b. Ibadah. As for Ali and Abbas, they
sat in the house of Fatima until Abu Bakr sent Umar to take
them out of the house of Fatima, and he (Abu Bakr) said to him
(Umar), “If they refuse, then fight them.” Thus, he (Umar) came with a
torch of fire to engulf the house on them and upon arriving, he
encountered Fatima. She said,“O Ibn al-Khattab, did you come to
burn our house?” He said, “Yes, unless you enter into what the
ummah entered into.”[Meaning paying allegiance to Abu Bakr]
al-Andalusi, Al-Aqd al-Farid, 4; 259
Ibn Abil Hadid reports that Fatimah said:
“O Abu Bakr, how fast you launched your strike on the family of the
Prophet after the death of the Prophet. By Allah, I will never speak
to you until I meet Allah!”
Sharh Nahjul-Balaghah, 2; 119
In fact, Fatimah did not talk to Abu Bakr until she died, as al-Tabari, al-Bukhari and al-Muslim have reported.
But threatening to burn the house was not all. In this assault on the household of the Holy Prophet, Fatimah al-Zahrah was injured and lost her unborn son Muhsin.
The prominent Sunni scholars mention the names of the individuals who took part in the attack on the home of the Ahl-ul-Bayt: Ubayd b. Hubayr, Thabit b. Qays, Muhammad b. Muslim, Khalid b. al-waleed, al-Mugheera b. Shu’bah, Abu Ubaydah b. al-Jarrah, Sa’d Mawla Abi Ubaydah, Ma’adh b. Jabal, Qunfud, Uthman, Abd al-Rahman b. Auf, Ziyad b. Ubayd, Mu’awiyah b. Abu Sufyan , and Amr b. al-Aas.
Later ahadith appeared, which try to justify the assault by saying that an opposition group gathered in the house of Fatimah, planning to act against Abu Bakr. But none of the prominent Sunni historians have mentioned this.
Furthermore Ahl-ul-Bayt were restricted in their economical means by usurping the land of Fadak from Fatimah which was given to her by her father.
The first as well as the second caliph refused to give Fadak back to her even though she employed various means to prove her entitlement.
Shia scholars do not accept the hadith on which Abu Bakr based the confiscation of Fadak from her as it goes against the teachings of the Qur’an.
Power was in the hands of people who opposed the right of leadership of Ali ibn Abi Talib. In order to legitimise their leadership they started an intense opposition and character assassination towards Ali.
For forty years, the leadership who bore deep animosity towards Ali,
forced mercenary speakers to ascend the pulpit and curse him in
addition to the daughter of the Holy Prophet and their children, Hasan
and Hussain. If anyone ventured outside of this jurisdiction and tried
to mention the virtues of Ali, they were warned that that was a crime
punishable by death.
Later on in time the hatred against Ali resulted in the Battle of Jamal, where for the first time, Muslims fought against one another and more than 20 000 Muslims lost their lives. After this bloodshed, Muawi’yah took arms against Ali in the battle of Siffeen with more than three times the casualties than in the battle of Jamal. When Muawiyah took the caliphate, he arranged the killing of the first grandson of the Prophet, Hassan ibn Ali.
50 years after the death of the holy Prophet, his grandson Hussain ibn Ali was mercilessly butchered together with his male family members and companions on the command of the son of Muawiyah, Yazid ,who was the tyrant ruler over the Muslim umma of that time.
So this was the relationship between Ahl- ul-Bayt and the top authorities of Ahl Sunna in the early years.