Yes the owner of the horse is a friend of mine. She has had him all her life and he has never had any symptoms. I was maybe thinking of buying him for WP as he is already showing. I doubt I'll do that now but I'm still riding him. I'm wondering what are the chances of him having a sever attack while I'm on him if he has never had an attack and is 7 years old? Do the attacks start small and progress to severe? I just downloaded the AQHA's HYPP survival guide but it is hardly helpful. BBUT it does say that sysmptoms usualy occur by three years old, if they are going to occur. Do you all agree?