Both the one who makes people holy and those who are made holy are of the same family. So Jesus is not ashamed to call them brothers and sisters. Hebrews 2:11
… “Here am I, and the children God has given me.” Since the children have flesh and blood, he too shared in their humanity so that by his death he might break the power of him who holds the power of death—that is, the devil— and free those who all their lives were held in slavery by their fear of death. Hebrews 2:13-14
God intends, through Jesus, to bring humanity to its intended destiny. Thus Jesus chose to share fully in our human condition. He accepted the sufferings to which all of us are subject as part of what it means to be of the “same family.” Jesus stooped to share all that we are, identifying fully with us, so that we might lift us up to share all that he is! We are of one family now, inheriting through our relationship with Jesus — our elder brother — the very life of God.