DS2's main issues are physical. He has severe hypermobility, uses a wheelchair most of the time and gets really tired. He also has meltdowns when he is tired or when he is scared and he has been diagnosed with mild sensory issues. The things that scare him are mostly noise related like parties and the car wash but also certain medical situations like the room in the dr surgery where they do the immunisations (the nurse at the dr surgery is really good and sees us in a different room for asthma checks etc) or anyone looking at his eyes. There are other children in his class who have more severe sensory issues than him but they are triggered by different things that DS2 is fine with eg change of routine or not winning the school raffle. There is also a little girl who has autism.
DS2 usually doesn't get invited to parties but occasionally he does and either he refuses to go or he goes and stands rooted to the spot just inside the door screaming until I carry him out. It usually takes 3 of us, one to carry him out, one to apologise and thank the host and one to be in the driving seat of the car, with the door open ready to drive off as soon as we dive in.
At the weekend there was a whole class party. Pictures on facebook etc. DS2 not invited but the other children with SN were and apparently had a great time. I just don't understand why DS2 can cope with changes at the last minute and isn't bothered when another child hits him on the head with a spade at school but can't cope with a party that children with autism/severe sensory issues can cope with.