Once Bitten, Twice Shy

After a potion's mishap, Snape is de-aged/deaged and becomes a 6-7month old baby and is put into the care of Sirius Black, his sworn enemy. Will the enemies be able to put the past behind them and allow the experience to heal ghosts from their past, or does the hurt just run too deep? Warning: Child abuse/neglect referenced. No slash. Kidfic!