Despite not even having reached her teens the youngster has two acclaimed BBC drama series to her name.
And the Glasgow girl can lay claim to having both David Tennant and Jason Isaacs play her dad.
She’s back as Jason’s daughter Marlee in the new series of detective drama Case Histories on BBC One.
And she starred alongside Broadchurch star David in Single Father.
“Jason’s such a fun guy,” Millie told The Sunday Post. “He has two daughters of a similar age so he was so easy to get on with.
“I was a little nervous at first but he made me feel at ease.”
Millie’s assured performances have seen her tipped for the top and she stole hearts and scenes in Single Father, which also starred Suranne Jones.
“David was lovely but not what I expected,” confides Millie.
“Obviously I’d seen him running around and larger than life in Doctor Who but he was very different in reality.
“He was quite quiet and reserved. He wasn’t used to working with kids but he was great.
“The secretaries at my old primary school used to ask if I had his number and whether I could set them up on a date.”
Isaacs returns as compulsive private detective Jackson Brodie, with Victoria Wood starring in the first episode as a retired copper on the wrong side of the law.
Brodie’s investigation takes him to the dark heart of a 1970s police corruption and murder case.
“I’m always away for tutoring when any of the adult scenes are being shot,” reveals Millie.
“But when we went to London for the screening of the first series there were a few scenes I wasn’t allowed to watch and I had to shut my eyes.”
Her mum and dad, Julia and Campbell, have been right behind their daughter’s career.
But while her primary school pals were used to her telly career she also starred in Tracy Beaker spin-off Dani’s House it’s different at high school.
“I started at Rosshall Academy last year and had a bit of hassle at first,” she admits.
“I was followed home a few times but it’s settled down a bit now.”
Millie has a major acting project in London over the summer but she’s keeping her feet firmly on the ground.
“My mum says if I get too big-headed it can be taken away as quickly as it came,” laughs Millie.
Case Histories, BBC1, Sundays, 8.30pm
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