I don't think Vito would have had a close relative murdered.
Vito refused to make his living exploiting women. Of course he did things that were just as bad but this showed he had some restraints.
Although his initial refusal to invest in drugs was primarily a business decision I think it's clear that there was some moral disdain there as well.
I used to think that Tom did the prostitute murder all by himself but the more I think about it the more I think that Michael set it up and gave the go-ahead.
"When the snows fall and the white winds blow, the lone wolf dies but the pack survives."
Winter is Coming
Now this is the Law of the Jungle—as old and as true as the sky; And the wolf that shall keep it may prosper, but the wolf that shall break it must die.
As the creeper that girdles the tree-trunk, the Law runneth forward and back; For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack.
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