Chloe's new reaction to Ben's seizure

This afternoon Ben had a seizure during his nap.  Chloe has seen Ben's seizures many times before.  She's never reacted to them much.  Today, she followed me into his room and while I was making sure Ben was breathing and watching him, I heard her crying behind me.  I asked her what was wrong and she said she was so sad for Ben.  She stood next to me, stroking his head during his seizure, crying.  I thought I had experienced all the pain that can be caused by Ben's seizures.  Watching my 5 year old daughter cry in empathy for her brother's pain is....  well, there are no words.  It is.  It just is.