Issac is very attuned to you, I believe. If the avian vet says Issac is healthy, how is your health and how are other things going? Perhaps he is seeing/feeling something attached to you. Just a thought. Check it out.
I don't think anyone thinks you have anything but good thoughts and great love for Issac and he for you. I have always been so touched by how devastated you were when he escaped once and how he came back looking for you, calling for you. I remember such a loving and unbelievable attachment. One frankly, I have always been quite jealous of.