One of Bree’s favorite books is Bark, George by Jules Feiffer. (Or “Bow-Goge”, as she says it.) It is about a dog who, when asked to bark, makes other animal noises instead. His mother, very concerned, takes George to the vet. The vet proceeds to reach into George’s mouth and remove several animals (including a cow!), after which George is then able to bark like a normal dog. For the moment. I won’t ruin the ending for you.
Bree would ask us to read this book several times a day, not taking “no” for an answer. She also has begun “reading” it to herself.