Hilary Duff has been in the industry for so long that most of her earlier films and TV roles are now nostalgic classics. Though she's since moved on to more "adult" roles (even if one is literally titled 'Younger'), many fans still point to her earlier work and budding acting talent.

Yet not every role earned critical acclaim.

Hilary Duff And Chad Michael Murray's Age Gap Was Iffy

One of many forgotten facts about the movie is the fact that Chad Michael Murray was quite a bit older than Hilary Duff. While she's in her 30s and he's in his 40s these days, at the time, Chad was a full-fledged adult while Hilary was totally underage.

When filming commenced on 'A Cinderella Story,' Hilary Duff was fifteen years old. Chad Michael Murray was twenty-two. While it's impressive (albeit not that rare) that Murray was able to pass for a high schooler at age 22, it's also somewhat problematic for fans who didn't realize the significant age gap at the time.

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If the two connected today, it would probably be pretty well-received (well, if Hilary wasn't married to Matthew Koma and Chad wasn't married to Sarah Roemer, that is), and the age gap would be very minor. But for a 15-year-old, to film kissing scenes with a 22-year-old seems a little uncomfortable.

Hilary Admitted To Crushing On Chad Michael Murray

Though it's a bit off-putting that an underage Hilary had kissing scenes with Chad in 'A Cinderella Story,' something that makes it even more awkward is the fact that Hilary later admitted to crushing on her co-star when they worked together.

Duff told Cosmopolitan years later that she "definitely" had a crush on Chad Michael Murray and that the kissing scenes had her "feeling pretty nervous." Then, she noted, they became friends, and that helped ease her nerves. Some sources say Chad took her out for a coffee before they started filming, to break the ice.

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But let's be real: in the non-Hollywood world, there are very few parents who would be OK with their teenage daughter (who's not even old enough to drive) going on coffee dates or kissing a 22-year-old.

The fact that they were working together is one thing, but again, couldn't the producers have cast someone closer to age 17 or even 18, given that the role of Austin Ames was that of a high school senior? Plus, another famous actor -- who happens to be one year younger than Hilary -- was even considered for the role but didn't get it. And yet producers couldn't find an actual teenager to fit the part.

Hilary's Crush Reveals A Wider Hollywood Problem

The thing about Hilary Duff's crush on Chad Michael Murray is that a crush alone wouldn't be an issue. It's the fact that they were co-stars, he was a lot older, and she had to kiss him on film that has heads turning these days. But the whole issue also reveals a wider Hollywood problem.

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Hilary Duff isn't the only young woman to be cast alongside a much-older romantic interest. In fact, Hollywood often casts on-screen couples with really wide age gaps, and it just feels wrong. Remember how Mila Kunis lied about her age, and it allegedly didn't come out until ages later, but now everyone's OK with her kissing Ashton Kutcher at age 14 while he was 19 because as adults they're currently married?

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Apart from uncomfortable on-screen age gaps that put minors in romantic relationships with legal adults, there's the other annoyance that fans often have with literally no actor actually being anywhere close to their character's age.

Even in the case of film couples like Julia Stiles and Sean Patrick Thomas, it's super awkward when fans realize that Julia was 19 at the time, and Sean Patrick Thomas was 31. At least Julia was a legit adult, but what would have been so wrong about choosing actual teens to play, well, teens?

Of course, that's Hollywood! Plus, back in the day, no one balked at Julia Stiles being cast as a high schooler when she was already 19, because she was a rising star. Obviously, Sean Patrick Thomas is super-talented and was overqualified for his role, even if his age didn't fit.

The same with Chad Michael Murray; swapping Chad or swapping Hilary wasn't an option, because their names attracted people to the film. So Hollywood glossed over their ages as part of the equation, and did what they wanted anyway.

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