Hmm.

You could argue that Vito (and the Family) kept Carlo close. In the book he was moved back to the mall and given a better position with the union. In the movie Vito even gives him a paternal pinch on the cheek.

Clemenza and Sonny keep Paulie close. Sonny inquires after his health and Clemenza brings him along for an important mission (of course the mission is different than what Paulie expects whistle)

Very few people ever really knew what Vito was thinking. I think Michael was just expressing Vito's maxim to play your cards close to your vest.

"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.