The Duke of Cambridge is wearing the stars of the Order of the Garter and the Order of the Thistle
The Prince of Wales is wearing the stars of the Order of the Garter and the Order of the Bath (of which he is grand master, and which he wears around his neck).
The Duke of Edinburgh is wearing the star of the Order of the Garter, and probably the star of the Order of the British Empire (of which he is Grand Master, and which he wears around his neck)
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