Murdered Portrait

On the morning of the fifth day, after the ninth death, I found her in the dining room, staring at the portrait. A rather bored looking 18th century guy stared back at her.

"You ok? I know you and the Professor were close, but the storm should be-"

"This is different."

I chose my next words carefully.

"I know you're stressed but you're not suggesting magic here?"

"What? No, of course not, it's hanging slightly differently."

As she said this, she pulled it down, revealing a blank wall.

Luckily she then smashed the frame and we found the poison supply.