Thank you for your answer which is very helpful. However, I got confused with your comment about "the rules on Potentially Exempt Transfers do not apply to you". I assume that this is a good thing and does not create any tax liability for my son?
You and your son simply do not have to worry about these as you are not living in the UK nor liable to UK tax. PETs, as they are known, are a trifle complex, but they do not apply to you. You may donate with impunity. It is, as you suggest, a very good thing.
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