This version of Mason is so last decade. (IFC Films)

The best description of parenting I’ve ever seen was in the comic strip “Zits” (that’s where I read it; the Internet suggests it originated elsewhere). It said simply, “The days are long, but the years are short.” At the time I read it, I had a chubby, blonde 4-year-old who was obsessed with Batman. Now I have a lanky, less-blonde 6-year-old who is obsessed with Batman. The Dark Knight is the only constant in my life as a mother.

My son is now the same age as Mason (Ellar Coltrane) at the start of “Boyhood,” the small miracle of a film that tracks a boy — and his family — over 12 years. Mason is so emphatically 6 in the beginning of the film that I couldn’t help compare him to my boy; one of the opening scenes has Mason giving his mother the perfectly logical explanation for why he tried sharpening rocks in the classroom pencil sharpener: He thought it would make sharp rocks. 

After we meet 6-year-old Mason, “Boyhood” starts hurtling along. He stretches, his hair darkens, his clothes start looking like things he picked out. Where people once chose for him, Mason begins making his own choices (many so remarkably stupid you wish he’d stuck to rock sharpening). And while I think the film is a half hour too long, there is always the underlying sense that this childhood is going way too fast.

It’s been a long time since a film has haunted me this much, not only because it felt like a glimpse into my son’s — and therefore my — future, but also because it holds a mirror up to life and reflects it so sharply it’s wonderfully uncomfortable. 

But what I remember most is desperately hoping that director Richard Linklater would do some sort of cheesy montage at the end, to go back, if only for a second, to the time before Mason could grow one of those scraggly teenage mustaches, back before he got interested in girls, back to when he could still fit at least semi-comfortably on his mom’s lap. That (to Linklater’s credit) doesn’t happen; “Boyhood” only moves forward. Mason will never be 6 again, except in the memories of those who watched him grow.

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