Autism and Neurotypical Siblings: Is There Room For Rivalry?

I know there may come a time when our girls fight like cats and dogs.  For now though, they are very close.  There have been some minor "sharing" issues but otherwise they prefer to be with each other over anyone else. Grace will often verbalize guilt over going places without Kate as I have spoken about before.  Kate, however, does not have the words so she reacts like in the video below.  Please don't think I am mean for posting this video of Kate crying because if you really listen you can tell she is 'turning it on' a little.  Kate is frustrated because she doesn't know where Grace is going (a visit to her grandparents for some Gracie time) and we can't yet explain it to her.  I feel terrible for her but rest assured she quickly settled when her dad came home until bedtime when she repeatedly asked for Grace again.  Eventually she fell asleep with Grace's pony and she was happy.  

I sometimes wonder if Grace has more patience for her sister because she knows Kate has difficulty navigating her day.  I wonder if maybe there is no room for rivalry in a relationship like this?  Grace has been fiercly protective of her sister at times but that is not what I am talking about as I have seen this in neurotypical siblings too.  I guess I am just wondering if others have found little rivalry between their NT child and their child with ASD.  You've seen how Grace treats her sister in videos I have posted here and here.  I would love to hear from other parents in the same situation.  

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