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In the picture above, it shows a scene in The Half-Blood Prince where Snape tells "Wormtail" to run along before shoving Wormtail into his room with a wave of his wand. Before Snape does, however, we are given a glimpse of Pettigrew's silver hand. If Snape knew this, why didn't he just suggest this solution to Dumbledore?
If he truly cared for Dumbledore, why didn't he just regrow the missing limb for Dumbledore instead of letting him die painfully, slowly, albeit surely?