Hi Chloe
I'm sorry this has happened to you. Yes, it is common for assessors to find any excuse not to award points. I'm not sure why she brought up no current social services involvement for your son. What has that got to do with anything? The claim is about you and your medical needs. He's also a child, so if she's expecting him to be your carer and saying you can obviously manage - that's just wrong.
I can imagine you're cross that the assessor misrepresented your ability to walk - but don't call the assessor 'a liar' however tempting or true it may be. Use comments such as "the assessor misunderstood ..."
BIS
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