Yes we should definitely act more like brothers and sisters than like enemies. Follow in Jesus footsteps.
Acting like brothers and sisters does not mean that we do not admonish our brother or sister when time is necessary. And I agree, we have to follow in Jesus' footsteps. All of them, even the ones which we would rather ignore.
"Go therefore, making disciples of all nations, baptizing them in the + Name of the Father, and of the Son, and of the Holy Ghost, teaching them *all* that I have commanded you. And behold, I am with you even unto the end of the age."
Notice He said "All"----not just the ones we would rather ignore, including the Holy Eucharist, the priesthood, sanctity of marriage and of life, etc.