Is there a religion where they don't kill their brothers under the guise of war?

Absolutely yes.

JW's do not go to war like other religions, which kill their brothers.

true Christians, who have their conscience trained by the Bible, do not learn war or participate in warfare.

As a result of holding to this Christian position, thousands of Witnesses, young and old, male and female, have been persecuted.

Many have suffered in forced-labor camps and prisons. During the Nazi era in Germany, some were even murdered.

Regardless of the vicious persecution they faced in Europe, the Witnesses never forgot their commission to preach the good news of Jehovah’s Kingdom.

They faithfully did so in prisons, in concentration camps, and in exile.

Later, Witnesses took no part in the warlike ethnic cleansing in Rwanda in 1994.

They also remained neutral during the bloodbaths that more recently occurred in the Balkans conflict during the breakup of the former Yugoslavia.

professed Christians often go to war against members of their own faith. Catholics kill Catholics on battlefields. Protestant kill Protestant.

a hundred million people have been killed in the wars of this 20th century, and all those wars have been supported by the religions of this world.

As a result, religious people have killed other religious people.

Much of the time, they have killed people of their own religion.

Catholics have killed Catholics, Protestants have killed Protestants, Muslims have killed Muslims, and those of other religions have followed the same course.

Jehovah's witnesses do not go to war or kill anyone especially not a brother which they have brothers and sisters all over the world.

Buddhism

Religion is an excuse to kill, not a reason. Some people want to advance their political agendas and religion provides a ready made audience for them to propagate.

None of the religions of Abraham.