"The Day of the Wedding (Bill Spillman)" joke

I heard this from a Welsh friend of mine,
Peter Gardiner, who lives in London.
It is the wedding day of Prince Charles and
Lady Di. Charles had been up late the night
before boozing with his old Navy buddies,
woke up late, threw on his clothes and rushed
to the Royal Coach and set off. In the coach,
he noticed that he had forgotten his shoes, so
he borrowed the ones his valet was wearing,
but they were 2 sizes too small.
Charles made it through the ceremony, then
through the reception with his feet in agony the
whole time, and finally with great
relief, went upstairs with his new bride.
Their departure was noticed by the Queen and
Queen Mother who followed them up and
listened at the the door. First they heard,
"Ohhh, ohhh, that feels so goood, it was sooo
tight."
"I told you she was," said the Queen to the
Queen Mother.
Then they heard,
"Ohhh, ohhh, ohhh, ahhhh, that feels even better,
and it was a lot tighter."
"Tsk tsk tsk," said the Queen Mother,
"Once a sailor, always a sailor."