Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
In a word, no. This constitutes a gift to you by your son and, as the UK has no gifts tax regime, it comes to you tax free. Just to be on the safe side make sure that he advises you in writing of this largesse.
I do hope that I have been able to set your mind at rest on this matter.
Thank you for your excellent support.
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