Oh no --- a close knit family not just some close knit group. Family members or brethren are blood relatives. Christians who refer to each other as brethren do so because of their born-again blood relationship --- the blood of the Lamb that they now all have in common and by which they are all saved and redeemed.
So you are saying then that those who partake of the Body of Christ and the Blood of Christ during the Mass are born again and saved, correct?
I basically agree -- the difference being tthat with the Sacrament of Baptism we are claimed for God and saved/born again without original sin.