Load of bollocks. It's an adult's handwriting.
I've spent enough years going through thousands of documents written by adults, children and medical professionals (yes, I could decipher the consultants' handwriting) through working in insurance, the NHS and in education to be able to tell the difference.
Being at my most optimistic, it's an adult writing a six year old's words. But in my normal headspace, it's an adult pretending to be a six year old to get a fuss made in the media and possibly a nice bit of crowdfunding carried out on their behalf.