Sadie Sink thinks she was a "mature" child star

She told AccessHollywood: "I think there was a certain maturity in me that I carried at a young age and I definitely subconsciously carry that into the role of Shelby. My experience was very untraditional, but so was Shelby's and I've found ways to marry the two."

In the play, Sadie stars as a high school student who previously had a relationship with a teacher and claimed that she had "learned so much" from her fellow cast members, and even though she is the lead, she insisted that there is "no star" in the play.

She added: "It's very surreal, it's such an ensemble piece - truly. There really is no star, and to be surrounded by everyone in this cast and to learn so much from them, that has been my biggest takeaway so far."

Sadie recently wrapped filming on the final season of 'Stranger Things' - in which she plays Max Mayfield - and admitted that she "cried so much" during her last days on set.

She told The Hollywood Reporter: "I haven't seen anything from it yet, I'm very curious though. It's going to be super emotional so I'm ready to cry with everyone.

"I had cried so much that my eyes were so puffy - they had never been like that before and there are some pretty embarrassing photos of me just with these giant puffy eyes."