I suspect these are the photographs Mark was referring to; the wedding of Elizabeth and Philip and the christening of Prince Charles.
The Dowager Marchioness of Milford Haven (née Princess Victoria of Hesse and by Rhine) is on the far right of the first pic and seated on the left in the second.
The lady in blue standing next to Queen Mary in the wedding photo is Prince Philip's mother, Princess Andrew of Greece, née Princess Alice of Battenberg. She was more recognisable perhaps at the Coronation a few year later, when she wore her nun's habit.
v Family Wedding Group, November 1947
> Christening of Prince Charles, December 1948
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