For me I was bullied more than the kid with the obvious disablity.  They were in a wheelchiar and could not walk at all and so people understood that one.  They knew what it was and knew it was wrong to bully them.  WIth my learning, behavioural and non visabled but physical disablity they were confused by me and so I was bullied a Lot.  I had a hip problem that would cause me more pain some days than others.  People could not understand why some days I could join in PE and others not, so they bullied me saying I made it up and I was lying.  It depends on how well you can hide the learning and other disablites.  If your learning disablity just comes across as making you thick you will be bullied for being thick.