True story told to me:
Grandfather said to his young grandson "Jump off that table and I'll catch you. Boy jumped and Granddad caught me.
"Jump again" he said, So the boy jumped a second time and Granddad caught me.
"Do it the third time" urged Grandad.
The boy jumped. Grandad didn't catch him and the boy fell to the floor, grazed his leg and burst into tears.
"Let that be one of the first sessions about life you learn" said Granddad. "Never trust anybody. Not even your own family !".