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  • All babies cry—and that’s a good thing. How else would we know if our helpless infants were cold, hungry, lonely or in pain? Traditionally, moms and dads have just been encouraged to keep their chins up and wait until the baby grows out of it. But, that’s easier said than done!

    Crying Takes a Toll on Babies AND Parents

    Typically, babies get increasingly irritable around sundown and can continue for hours. No wonder, parents get concerned, frustrated and very, very tired.

    Exhaustion triggered by persistent crying creates huge stress in families, including marital conflict, maternal and paternal depression and obesity. It causes car crashes and other accidents—people make all kinds of poor decisions when stressed and overtired. It also puts babies in danger when a wiped-out parent falls asleep with a baby in his arms, on an unsafe couch or a bed, which increases the risks for SIDS and infant suffocation. And believe it or not, the national costs of complications of infant crying and parental exhaustion total well over $1 billion dollars a year! 

    My ‘Aha!’ Moment on Calming Babies

    Most doctors say that colic (crying for more than 3 hours a day) is a mystery. That’s what I used to say, too, until 1981 when I learned about the !Kung San of the Kalahari Desert, whose mothers usually calm their fussy babies in under a minute! The more I thought about it, the more I realized we could be as successful as !Kung parents, but only if we adopt 2 new ideas:

    1. All babies are born 3 months early. Newborn horses can run within an hour of birth but not our mushy little babies. A virtual 4th trimester of womb sensations (soft touch, jiggly motion, snug holding, etc.) may just be what they need.
    2. The rhythms experienced inside the womb trigger a reflex that keeps babies relaxed. This calming reflex is a virtual off-switch for crying and on-switch for sleep.

    The !Kung mothers are master baby calmers because they imitate the womb by carrying and rocking their babies 24/7...and feeding them 3 times hour. American parents have long turned to similar womb-mimicking tricks, whether they’ve realized it or not, like going for car rides and turning on the vacuum cleaner to soothe their babies. In fact, smart parents around the world have invented all kinds of variations on the calming womb-like sensations I’ve dubbed the 5 S’s: Swaddle, Side-Stomach Position, Shush, Swing and Suck.

    The basics of the 5 S’s method are below, but complete guidance can be found in my Happiest Baby on the Block book and companion DVD/Streaming Video.

    The 1st S: Swaddle

    Swaddling recreates the snug packaging inside the womb and is the cornerstone of calming. It decreases startling and increases sleep. And, wrapped babies respond faster to the other 4 S’s and stay soothed longer because their arms can’t wriggle around. To swaddle correctly, wrap arms snugstraight at the sidebut let the hips be loose and flexed. Use a large square blanket, but don’t overheat, cover your baby’s head or allow unraveling. Note: Babies shouldn’t be swaddled all day, just during fussing and sleep.

    The 2nd S: Side or Stomach Position

    The back is the only safe position for sleeping, but it’s the worst position for calming fussiness. This S can be activated by holding a baby on her side, on her stomach or over your shoulder. You’ll see your baby mellow in no time.

    The 3rd S: Shush

    Contrary to myth, babies don’t need total silence to sleep. In the womb, the sound of the blood flow is a shush louder than a vacuum cleaner! But, not all white noise is created equal. Hissy fans and ocean sounds often fail because they lack the womb’s rumbly quality. The best way to imitate these magic sounds is white noise. Happiest Baby’s CD / Mp3 has 6 specially engineered sounds to calm crying and boost sleep.

    The 4th S: Swing

    Life in the womb is very jiggly. (Imagine your baby bopping around inside your belly when you jaunt down the stairs!) While slow rocking is fine for keeping quiet babies calm, you need to use fast, tiny motions to soothe a crying infant mid-squawk. My patients call this movement the “Jell-O head jiggle.” To do it, always support the head/neck, keep your motions small; and move no more than 1 inch back and forth. I really advise watching the DVD to make sure you get it right. (For the safety of your infant, never, ever shake your baby in anger or frustration.)

    The 5th S: Suck

    Sucking is “the icing on the cake” of calming. Many fussy babies relax into a deep tranquility when they suck. Many babies calm easier with a pacifier.

    The 5 S’s Take PRACTICE to Perfect

    The 5 S’s technique only works when done exactly right. The calming reflex is just like the knee reflex: Hit one inch too high or low, and you’ll get no response, but hit the knee exactly right and, presto! If your little one doesn’t soothe with the S’s, watch the Happiest Baby DVD / Streaming Video again to get it down pat. Or, check with your doctor to make sure illness isn’t preventing calming.

    How Do the 5 S’s Relate to Another Favorite S – Sleep?

    The keys to good sleep are swaddling and white noise. In another "Aha!" moment, I realized technology could assist parents with their 4th-trimester duties. So Happiest Baby invented SNOO, the world’s 1st smart sleeper—an innovative baby bed based on the 5 S’s that helps calm babies and ease them into sleep. Parents especially love when it quickly calms babies for those 2 a.m. wakings!




    1. Happiest Baby Staff September 15, 2017 at 09:50 AM

      Hi Pam,
      Congratulations to you and your family! SNOO is so helpful to parents of twins—an ‘extra set of hands’ to help out 24/7. However, it is not safe to place more than one baby in SNOO at a time; each baby will need their own SNOO. We have even had quintuplets sleeping in their own 5 SNOOs…one right next to the other!

      If you’re using 2 SNOOs or more in the same room, we recommend spacing them at least 1 foot apart. Please contact if we can help answer additional questions!

      The Happiest Baby Team

    2. Happiest Baby Staff August 29, 2017 at 11:06 AM

      Hi Kanisha,
      SNOO Smart Sleeper can be used for up to 6 months. It delivers 3 of 5 S’s to calm crying and boost sleep and gives parents more peace of mind than ever before (because they know their baby can’t roll to a risky position.) And, it quickly gives most families 1-2+ hours sleep a night! Trying it is easy, we offer a 30-day risk-free trial, free shipping and the option to buy now…and ship whenever you want.

      If you’re expecting, or if your baby is of the right age, we hope you choose SNOO. We think you’ll be very glad you did!

      The Happiest Baby Team

    3. Kanisha Agarwal July 27, 2017 at 07:19 AM

      What is the maximum age till this sleeper can be used?

    4. Pam June 22, 2017 at 05:15 AM

      My son and daughter-in-law are expecting twins. Can two newborns sleep together in a Snoo?

    5. Gricel Beltran-Taj February 14, 2017 at 01:54 PM

      We were lucky enough to have a friend recommend “The Happiest Baby on the Block” book before our baby was born. As soon as she was born, we implemented the 5 S’s – this was 4 months ago- and to this day, I can say we truly have the happiest baby on the block! Other than when hungry, she has never cried! Our lifesaver S’s were swaddle, Shushing (white noise machine), and the swing! Thank you Dr. Karp for these wonderful tools! Every parent should read this book before baby arrives- it is truly a lifesaver!

    6. Lauren January 9, 2017 at 01:54 PM

      Just finished reading your book and found it so helpful!! I have a question though… when I swaddle my baby she tries so hard to get her hands out even after we lay her down! She thrashes until she succeeds (and sometimes she does!). She’s only 2 weeks old. I’m not sure I can make the swaddle any tighter! Any suggestions? She’s a preemie approaching her due date and her crying is definitely getting worse!!

    7. Melissa | Baby Castan on Board January 9, 2017 at 07:32 AM

      The day after we took our little guy home we left him unswaddled and we paid the price that night. He did not stop crying from 4pm-1am. I happened to remember a book that a friend passed along (what a lifesaver). Once we swaddled him and did the 5 s’s from Harvey Karp’s The Happiest Baby on the Block he stopped immediately and we were able to calm him to sleep.

    8. Olivia September 26, 2016 at 11:33 AM

      I didn’t know about the 5 S’s and I love the whole system and it works very well! I tried it today and my little guy calmed down considerably faster than usual. I’ve also started using white noise a few weeks back and it is great at relaxing him and me as well :).

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