Optimize Your Opener Entry #4 (I skipped #3, as my colleague is doing that one as a guest editor on this blog)

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The shriek that exploded from the little [LITTLE COULD BE 1 OR 6 -- YOU SHOULD BE MORE SPECIFIC THAN VAGUE IN FIRST PARAGRAPHS] girl’s lungs was one most parents would describe as ‘loud enough to wake the dead.' It didn’t work this time. [SORRY, BUT I DON'T KNOW WHAT THIS PREVIOUS SENTENCE IS SAYING.] The screeching jolted her mother out of a seat on the park bench nearby. Bundled up against the cold in clunky winter boots and a bulky down coat, she whirled around like a Michelin Man ballerina [WHILE CUTE, WHAT DOES THIS METAPHOR HAVE TO DO WITH THE SCENE? IS IS SUPPOSED TO SOFTEN THE TENSION BY ADDING HUMOR? IF YES, OK, BUT IF NO, RETHINK YOUR METAPHOR -- PERSONALLY, I THINK IT FALLS FLAT], her eyes searching the park for her daughter.

“Ashley?” The woman’s head snapped toward the river, unsure where the sound had come from. No answer, just more screaming from that direction. [BUT SCREAMING IS AN ANSWER] Adrenaline surged through her body as she sprinted for the riverbank as fast as her [NOPE. DON'T SAY 'AS FAST AS' IF SHE'S ACTUALLY STRUGGLING DUE TO CLOTHING. SHOW HER TRIPPING OR SOMETHING THAT SHOWS US THE CLOTHING IS IN THE WAY] cumbersome clothing would allow. “Please God, don’t let my baby drown,” she prayed in a frantic whisperED.[YOU'VE DONE A GOOD JOB 'SHOWING' SHE'S FRANTIC, SO YOU DON'T NEED TO 'TELL' US]

1) I think this is supposed to be a suspenseful opening, but the author has shot him/herself in the foot in a few places:
a) The first line is written in a passive voice, as if looking back on the incident, which removes us, not embeds us, from the story. The action is thus watered down immediately. Worse, this style is common to humor, so sets an expectation. In fact, the first 2 lines made the story sound more like a comedy to me.
b) The second line is vague. Frankly, I don't what it means. Does the "it" refer to her screaming for help? Or waking the dead? The latter would imply a paranormal story.
c) The metaphor is awkward, if not silly, for this type of work. You have to choose metaphors to play to your genre, the action, and the character. This metaphor implies humor/ridiculous, which I doubt the author intends. Although it's supposed to set us up for mom's inability to move quickly in paragraph 2, where we again get info on her clothing, it just stands out awkwardly. Like a giant Michelin Man in a crowd. We really only need to hear about the clothing issue once. Save the precious space for something more important.
d) The mom is sprinting toward the river, but the sentence is dragging. You always want your sentence and your action to match. Fast action means short, direct sentences with verb/noun construction. You're close, so just edit more. See comments above.
2) The story opens implying POV is with the kid, but it's really with the mom. That first sentence should be reworked to be told from mom's POV. YOu should establish a clear POV for the book from the first paragraph.
3) Overall, I think it's smart for this author to open their book with an action scene of the daughter being abducted (if this is really the case). But don't rely on the kid/mother relationship to impart "heart" into your story -- most readers have seen this situation in movies/books a million times. We have to care about the characters, not the situation. What unique characteristic would make us care about either the mom or the kid immediatley?