"I wonder," Severus mumbled as he walked over to the sleeping first year and cast a diagnostic charm. "Meddling old fool." He cursed. "Dumbledore placed a compulsion charm to prevent Creevey from coming forward when he got suspicious of the diary. That combined with Colin's light magic mixing with Tom's dark magic and broken soulbond has caused instability in his core. We are lucky he didn't blow up the castle when he lost control."