In 1936, following his brother's abdication, the King tells his daughters always to put the country above personal interests and nineteen years later this comes back to haunt Elizabeth as, although Margaret is now twenty-five, Parliament finds new objections to her marrying Townsend, chiefly because he is a divorcee, and the Queen is put in the terrible position of having to break her promise to her sister and forbid the marriage. Margaret hates her but a phone conversation is made with surprisingly sympathetic Duke of Windsor. Another problem is Philip's continued view that he is always in his wife's shadow as he goes off to open the Melbourne Olympics - and in Egypt the Suez crisis looms.
—don @ minifie-1 with clarifications by d.rust