Funny postscript to that anecdote: Hussey was not allowed to attend the premiere of Romeo & Juliet, because it contained nudity, and UK law at the time prohibited anyone underage from seeing movies with nudity.
An audience of grownups were allowed to see Olivia Hussey nude, but not Olivia Hussey.

Exactly. Olivia Hussey was 15 when she made Romeo and Juliet but her parents consented and her (very tastefully done)nude scene was filmed on a closed set.
Don't judge my path if you haven't walked my journey.

Nudity is not pornography.
Thora Birch was 16 when she shows her breasts in American Beauty. Jenny Agutter was full nude in Walkabout, she was not an adult either. Someone else mentioned Blue Lagoon.
Depending on the laws of the country, and if the parents consent, you can show underage nudity if it's not pornographic.

There is a difference between mere nudity & pornography. She does practically the same & more in "Blue Lagoon" remake.

In the 1997 movie Lolita they used a body double and skin colored suits to for their scenes with supposed underage nudity.

Maybe Roman Polanski came in to direct those scenes.

And He has on His robe and on His thigh a name written:KING OF KINGS AND LORD OF LORDS.

If those scenes were filmed in the UK, perhaps different laws there pertaining to this?

It was only her ass and a little nipple