Mara made her film debut at the age of six in Mrs Doutbfire and appeared in movies including Miracle on 34th Street and Matilda before retreating from Hollywood.
Better than most, she has an in-depth understanding about what happens when a child star matures, and has shared her thoughts in a breezy but thoughtful essay on Cracked.com titled "7 Reasons Child Stars Go Crazy".
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Mara, who is now a 25-year-old writer, begins by putting the focus very much on the parents. In her first point, "Their parents won't help them", she reveals how she decided to get into acting age five and that her mum and dad tried hard to discourage her.
"When I insisted, they allowed me to act, but were always very protective of me," she writes.
"I saw many child actors who did not have that, and they were all miserable. Kids whose parents pushed them into acting often grow up reseting them. They never had a choice, and worse, they never had the chance to be a kid."
In her second point, "Their parents can't help them", Mara draws attention to Miley Cyrus and her father Billy Ray, who admitted in 2010 that he had very little control over what the Hannah Montana star did.
Mara starring in Matilda
It's a problem that extends right across Hollywood. Just this weekend, Amanda Bynes claimed she would rather that her parents, who she know longer speaks to, "be homeless than live off my money", and Macaulay Culkin has a well-documented troubled history with his family, and is currently estranged from his father.
Mara also refers to a child star's inevitable fall from favour — "They get used to love and attention, and then lose it".
"The first week of my first movie, Mrs Doubtfire, I got gift from every cast member," she begins. "…Combine the amount of free stuff celebrities get with all the presents people give kids just for being cute, and you've got a recipe for one spoiled-ass child.
"Adults know that infatuation is fleeting, but kids don't understand this. A year in a kid's life seems like an eternity, and they think anything happening now will happen forever. Years of adulation and money and things quickly become normal, and then, just as they get used to it all, they hit puberty – which is a serious job hazard when your job is being cute.
"A child actor who is no longer cute is no longer monetarily viable and is discarded. He or she is then replaced by someone younger and cuter, and fan bases accordingly forget that the previous object of affection ever existed."
Stating that child stars "can't rebel" and so often act out in their late teens and early 20s, Mara also says famous youngsters, "don't know what else to do", and uses Lindsay Lohan — currently completing an enforced stay in rehab — as an example.
"If I were to talk to Lindsay Lohan, I'd encourage her to get the hell out of acting and into something soothing," she writes. "Take up botany or something.
"It because she's been acting all her life, she has little education, and in her mind, there's nothing else she can do. She's likely to keep doing it even if she's making herself — and also maybe the people she world with — miserable."
In her final point — "They can't escape it" — Mara says that while she has done all she can to avoid to limelight, she does occasionally still get recognised and this has given her something "not only to live up to, but surpass."
Public recognition bring pressure, she says, but none more so than the feeling a lot of child stars develop that "they'll never get past what they did as a kid, that their character has taken over their life."
"People who meet me as an adult are often surpassed that I'm alive and have never been in prison or rehab. Sometimes they're disappointed I'm not cooler…," she writes.
"There's not much to do besides accept it for what it was and move on. Child stars who are best off as adults usually do one or two projects, then get the hell out of Hollywood, at least for the next few years."