### What? `previousValue` was incorrect. It would always return the current value. ### Why? It was accessing siblingData instead of siblingDoc. Other hooks use siblingDoc, but this one was using siblingData.
### What? `previousValue` was incorrect. It would always return the current value. ### Why? It was accessing siblingData instead of siblingDoc. Other hooks use siblingDoc, but this one was using siblingData.