John 19:25 Standing by the cross of Jesus were his mother, his mother’s sister, Mary the wife of Clopas, and Mary Magdalene.
John 19:26 When Jesus saw his mother and the disciple he loved standing there, he said to his mother, “Woman, here is your son.”
John 19:27 Then he said to the disciple, “Here is your mother.” And from that hour the disciple took her into his own family.
taking care of each other
Jesus’ love for his mother and for John is seen here in the fact that even as he is in agony on the cross, he brings these two lonely people together to take care of each other. Jesus cares about our needs – even our need for family.
Verse 27 literally says “the disciple took her into his own (ἴδιος).” The word is twice used in John for family relationships.
Andrew found his own brother (1:41)
Jesus said God was his own Father (5:18)
So, it is my opinion that John was talking about adopting Mary into his family. Granted, Mary had other children, but I think that is why Jesus did this. He wanted these two believers to invest their lonely lives in each other.
That is what church fellowship is all about too. It pleases our Lord when we take care of each other.