I see. Thank you for the replies.
The thing is however, that it says your hp increased by %, not that your mount hp added to yours. Also I have dropped before down to almost no hp while mounted and never had mount die, this is the first. I dont think that the hp added to my health bar is the mount hp because if that was the case then once that is lost mount would die, no? Can't figure it out. Of course I bought another one, but still. I have played with my horse from like 6 to probably 22 and never had him die. My tiger however dropped in like 4 levels then. Doesn't make sense.