Ever since Corrine from The Bachelor revealed she still had a nanny, it’s become a running joke to talk about adults having a nanny.

Emma Watson interviewed one for herself as part of a prank on The Ellen DeGeneres Show on Friday.

The 26-year-old questioned the unsuspecting girl while DeGeneres secretly instructed her what to say via hidden earpiece.

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If it’s good enough for Corrine: Emma Watson interviewed a nanny for herself as part of an Ellen prank on Friday

‘Okay so I’m looking for a nanny, but here’s the thing… you’d be my nanny,’ the Harry Potter star informed the oblivious victim.

‘I got the idea when I was watching the Bachelor… I started saying “vagine” too.’

The nervous nanny giggled and nodded in agreement, unaware she was really being remotely interviewed by the host.

‘I’m very particular… I don’t like crusts on my sandwiches. I don’t like milk, but I like Red Bull,’ the actress repeated while somehow keeping a straight face.

Ellen in you ear: The 26-year-old questioned the unsuspecting girl while DeGeneres secretly instructed her what to say via hidden earpiece

Hidden camera: ‘Okay so I’m looking for a nanny, but here’s the thing… you’d be my nanny,’ the Harry Potter star informed the oblivious victim

‘I like to go potty alone… I don’t need you to help me potty.’

Ellen then told Emma to disclose: ‘I want to be able to trust you with my secrets, so I’m going to tell you something right now that I’ve never told anyone….’ before leaving the pair in a lengthy awkward silence.

On Ellen’s instruction, Emma then suddenly burst into tears. ‘My finger really hurts… it’s an owie. Can you make it better?’ she said offering a digit for the mortified nanny to rub better.

Inspiration: ‘I got the idea when I was watching the Bachelor,’ she said. ‘I started saying “vagine” too.’

Oblivious: The nervous nanny giggled and nodded in agreement, unaware she was really being remotely interviewed by the host

‘That was a test, you did very well,’ Emma told her, snatching it back.

The Beauty And The Beast star then realised it was snack time – fetching an enormous lillipop from the cabinet – before tossing her phone across the room in a tantrum.

‘Mirror mirror on the wall, who’s the best little girl of all? You are Emma… you are,’ she told herself, as she struggled to keep the laughter in.

Awkward: Ellen then told Emma to disclose: ‘I want to be able to trust you with my secrets, so I’m going to tell you something right now that I’ve never told anyone….’ before leaving the pair in a lengthy awkward silence

Want some? The Beauty And The Beast star then realised it was snack time – fetching an enormous lillipop from the cabinet – before tossing her phone across the room in a tantrum

Earlier on the show, Ellen poked fun at the dress Emma had worn to her very first movie premiere of Harry Potter And The Philosopher’s Stone in 2001.

‘My mom and I planned this for weeks,’ she said of the sack-esque ensemble. ‘It doesn’t look like it, but there was a lot of thought that went into this.

‘I thought i looked amazing by the way,’ she added, ‘bless me.’

The actress also discussed being cast as Belle in the upcoming Disney live action reboot.

Breakin character: ‘Mirror mirror on the wall, who’s the best little girl of all? You are Emma… you are,’ she told herself, as she struggled to keep the laughter in

Thank God! She eventually let the ‘nanny’ in on the secret

‘If you had told me when I was five – which was probably around the age that I was watching it on repeat – that i would one day get to play belle from beauty and the beast, I don’t know what I would have done, she said. ‘A) I wouldn’t have believed you, and B) I would have freaked out

‘I watched that so many times i made my parents crazy… like so many times!

As for her depiction of the heroine she insisted: ‘It was very important to me that she be very active and in control of her own destiny, and i wanted her to be powerful… I mean she already was to be honest.’