Preparing to celebrate Mom on her special day, you may search for just the right eye-watering Hallmark stanza, make reservations at her favorite restaurant or pick up a bouquet of flowers.

But, this Mother's Day, help cultivate appreciation for the woman responsible for your existence by considering the worst in motherhood portrayed on the big screen.

Still upset about that time your mother grounded you for wrecking her car? Does even the thought of her using your full name send shivers down your spine? That's nothing compared to the worst Hollywood has to offer.

From an actual monster to the simply monstrous, from a narcissist to the downright nasty, the following cinematic terrors were birthed from the imagination (and memory) of famous storytellers, filmmakers and embittered children.

Here's an overview of the top five scariest movie mothers of all time ...

No. 5: Mrs. Bates, "Psycho" (1960)

In this Hitchcock horror classic, Mrs. Bates is the matriarch of the Bates Motel, a roadside dump where on-the-lam screen sirens check in and never check out.

Meet Marion Crane (Janet Leigh). She's an unmarried woman of a certain age involved with a debt-ridden pretty boy. What's a girl to do? Marion steals $40,000 and goes on the run, checking into the Bates Motel. There she meets Norman Bates, a seemingly nice boy with serious mommy issues.

Later, in the infamous shower scene, Marion is stabbed to death by a gray-haired figure in a dress, presumably Mrs. Bates. An ill-fated private detective tracks Marion to the motel, and "Mrs. Bates" gets all stabby with him too.

Meanwhile, Marion's sister and the pretty boy show up and discover that Norman's mother is actually a corpse kept in the root cellar whose prior personality was absorbed by her serial killer son. This is one mother-son bond that not even death could put a damper on.

No. 4: Mary Brady, "Sleepwalkers" (1992)

Meeting the mother of the boy you're dating can be stomach churning, but never more so than in this campy horror flick based off an original Stephen King screenplay.

For girls dating Mary Brady's son, an introduction to Mom will suck the life out of you, literally. Mary and her son are demonic shape-shifting creatures that survive by extracting the life force of virgins, leaving their victims as shriveled, parched cadavers. This gruesome twosome is vulnerable only to the scratch of a girl's best friend, the house cat.

When Mary's not having disturbing slow dances with her son, she's attacking him in a jealous frenzy, and when he doesn't provide sustenance fast enough, she thrashes him further.

But when her son is threatened by a gutsy local virgin, Mary exacts a bloody revenge, slaughtering the girl's family and dismembering the local police force before finally succumbing to the claws of a neighborhood feline.

No. 3: Joan Crawford, "Mommie Dearest" (1981)

As portrayed in this bio-pic based on the autobiography by Joan Crawford's adopted daughter Christina, Crawford is a mentally unstable narcissist who uses her adopted children as shiny props to make her appear loving to the press.

Crawford is consumed with perpetuating a glamorous Hollywood persona, but she unravels as her daughter grows into a young woman and her own beauty and fame fade.

In the movie's most emblematic scene, Crawford inspects her sleeping daughter's closets, suddenly roaring, "No wire hangers!" She tears every item from her daughter's closet and then flogs the small child with the offending hanger. The mother-daughter horror show then moves to the bathroom where Joan forces Christina to scour the floors, finally leaving her traumatized daughter in a sea of powdery Clorox.

Crawford's final gift is to cut Christina and her brother out of her will.

No. 2: Margaret White, "Carrie" (1976)

In this horror classic directed by Brian De Palma and based on a Stephen King novel (between this and "Sleepwalkers," kinda makes you wonder how he got along with his mom, huh?), Margaret White is Carrie's insanely pious mother.

When Carrie begins her menstrual cycle, Margaret slaps Carrie with a Bible and forces her to pray for forgiveness locked inside a closet stuffed with gruesome religious artifacts. But these new energies in Carrie have awakened a supernatural power, the ability to move objects, and she learns to use her power to keep Margaret at bay.

When Carrie puts on her slip-like prom dress, Margaret tells her, "I can see your dirty pillows. Everyone will. They're all gonna laugh at you!" Sadly, Margaret was right, they all did laugh at her.

After a bucket a pig's blood is poured on her head, Carrie harnesses her telekinetic abilities to inflict a prom night massacre. "Hold me, Momma," Carrie begs, after making it home. Instead, Margaret stabs her with a butcher knife.

No. 1: Mary, "Precious" (2009)

Based on the novel "Push" by Sapphire, "Precious" co-stars Monique in an Oscar-winning role as an appallingly abusive mother.

Mary is furious that Precious is pregnant with her second child (from her father). In between the beatings she delivers, Mary asks, "Just because he give you more children then he give me, you think you something special?"

Throughout the film, Mary doles out brutality and insults to Precious like they're Halloween candy, including gems along the lines of, "Don't nobody need you. Don't nobody want you."

After delivering the baby, Precious returns home and Mary celebrates the occasion by throwing the infant on the floor and hurling a potted plant and TV at her daughter.

At the end of the movie, when a social worker asks why she did nothing to stop the abuse, she replies, "Who else was gonna love me?" Who indeed?