Which law?
The people surrounding Jesus feared for their lives. They ran and abandoned Christ. They thought they would be next. I believe James, Jude, Simon, Joseph and others all abandoned Christ in His time of need. Peter certainly did. All the Apostles ran. Mary did not run. John was there. Mary was alone at the foot of the cross and her other children were in hiding. Jesus entrusted Mary to the one who did not abandon him. Jesus saw those who followed him as his true mother and brothers and sisters. He gave John the responsibility of caring for Mary. John was Christ's brother in spirit. The others were as of yet unconverted.
I have no idea what you are talking about.
Yes, His disciples abandoned Him.
His close relatives (cousins) never believed Him, but they didn't abandon Him because they were never with Him. NOWHERE does it say that Mary's "other children" were hiding, because there weren't any.
Nothing you say indicates that Jesus had any brothers or else Mary would have been entrusted to them.