I have two children, the older one (19) a birth child and the younger (13) an adopted child.
Wen my older child was about 14 he was very troubled and tried to take an overdose. At the hospital, he told he nurse I bullied him, which I did not.
Social services opened a file and investigated, they spoke to the school and after a short while were satisfied that all was well and closed the file.
My child was having some significant mental health issues and I think telling the nurses that I bullied him was a kind of release for him. I was quite upset but I also realised my child was acting out in a certain way (he is on the autistic spectrum).
I hope that my son did learn that telling stories about what has happened is really unhelpful and even dangerous.
We made our peace and it has never happened again.
I don't know if that helps you at all but hopefully schools are wise enough to know that children do sometimes lie about things. The school did need to investigate in whatever way they do because they needed to be reassured that all was well. And now they know it is.
But try not to be too upset because it probably is more common that one would imagine, for kids to make things up.
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