The actress reveals her cash-strapped father, Robert, would only drive her to try-outs if she knew all her lines.
"We did not have enough money for gas and so dad wouldn't drive me in (to London) unless I knew every line," she tells BBC News. "I was desperate to be on camera."
The 16-year-old, who grew up in Bournemouth, England, insists her humble beginnings have kept fame from going to her head.
"I don't think I've ever looked at myself and thought I'm famous," she added.
Brown is currently promoting her new Netflix movie "Enola Holmes".
Brown rose to prominence after starring as Eleven on Netflix's popular sci-fi horror series "Stranger Things". At age 13, she became one youngest nominees in Emmy history after receiving a Primetime Emmy Award nomination for Outstanding Supporting Actress in a Drama Series in 2017 for her role on the show.
Now blessed with the abundance of financial gains from her acting gigs, the British actress didn't forget to give back. In April of this year, she announced on Instagram that she and her family had donated 20,000 meals each to food banks in New Mexico and Atlanta.
"While we stay home and do our part to flatten the curve, we must not forget those in need," she wrote at the time. "My thoughts are with the great people and crew from Santa Fe, NM whom we didn't yet get to meet in our company move on 'Stranger Things.' In appreciation of this community, my family and I have donated 20,000 meals to The Food Depot, which will provide meals for those hungry in the Northern New Mexico service area."
She added, "Also, to all those in Atlanta who have embraced us, to the ST crew and their families, you're in our thoughts. My family and I have donated 20,000 meals to the Atlanta Community Food Bank, which will provide meals for those hungry in their service area."