Hi giulia_foster_mom, Good day! The spinning motion makes this flutter, so I would recommend taking it out and placing it back in to see if that fixes it. Thanks,

I imagine a 12 lb dog could play with this since my 17 lb cat does. LOL!

No, unfortunately, it doesn’t have a timer on it. But that should be a suggestion to the manufacturers. 

I just went through the same ordeal, I bought the unit with 2 Butterflies and in a week or so both were bent. I took the Butterfly off the base and the secret to getting it straight is to look for the hook that secures the butterfly to the plastic piece , Get 2 Plyers one to hold the hook on the base , and the other Plyer on the top of the base where the wire goes up to the butter fly. Slowly bend that back into place and BAM , you have a working butterfly not dragging on the floor.

if you look on the back of your box, it gives you a sku number to look up so you can order them :) if you don’t have your box anymore just visit the store to get the sku off another box :)

At Petco but online the stores by me don’t carry them!

I bought replacement butterflies on the Petco site... And thank goodness they we're available because my kitties LOVE this toy....it's adorable to watch as they have much they have fun with it.