Hayley Mills had no idea shed won an Oscar until it arrived on her doorstep.

But not only did she miss the 1961 ceremony, she didnt realize it had occurred at all.

I didnt know very much about the Oscars, Mills admits.

Hayley Mills

Loomis Dean/The LIFE Picture Collection/Getty Images

I didnt know very much about anything, really.

So it was all a big surprise.

Of course, Mills has a much clearer understanding now, at 71, of what her achievement meant.

Hayley Mills And Jane Wyman In ‘Pollyanna’

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ENTERTAINMENT WEEKLY:Pollyannawas the first of six features you made with Walt Disney.

I worked with wonderful, experienced actors and actresses and excellent directors.

I started acting at a time when children were younger.

I dont think we grew up as quickly.

Do you have any fond memories of your time onPollyanna?MakingPollyannawas a wonderful experience.

It was what I was familiar with.

We stayed in the famous Chateau Marmont hotel in those little cabins and looked down over Sunset Boulevard.

California and Hollywood in those days, it was magic for a child.

She was warm and sweet and kind and lovely to me.

And Karl Malden used to make me laugh a lot.

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Id never seen such amazing looking American food, and I was distracted to say the least.

They didnt get a single shot in the can in the morning.

They did eventually and you went on to win the juvenile Oscar.

At the ceremony,Annette Funicello accepted the trophy on your behalf from Shirley Temple.

Like, Oh, thats sweet.

I thought, My God, Im actually a part of this!

I hadnt ever felt that connection, and it was extraordinary.

My heroes were on that stage with me, and I was considered to be one of their number!

And you know, its not something you’re able to replace.

Theyve broken the mold.

[Laughs] They said, Im sorry, it doesnt work like that.

At the time, how did winning the Oscar affect the way you viewed your career?

AfterPollyanna, you went on to make more hits likeThe Parent Trap, before successfully transitioning into adult parts.

Youre now in the Off-Broadway playParty Face.

It wasnt always clear to me where I should go, and where the path was leading.

And then I brought my then-1-year-old son with me on location, and it was miserable for him.

It was in the middle of winter in the north of England, and it rained constantly.

Im very good at being out of work.

I am so surprised and so grateful that I am still paying the bills by doing this!

Mills is now appearing off-Broadway inParty Faceon Stage II at City Center through Apr 8, 2018.