• The 5 Step Test: How to know if a child can ride safely WITHOUT a booster
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Why these 5 steps?

A booster’s job is to:

  1. Make the child’s body fit properly on the vehicle seat AND
  2. Make the seat belt fit properly on the child’s body.

Steps 1 and 2 look at whether the child’s body fits properly on the vehicle seat. Steps 3 and 4 look at whether the seat belt fits properly on the child’s body. Step 5 looks at whether the body and belt will be in the right position should a crash occur. Therefore, saying yes to all 5 steps means that the body and belt will fit properly WITHOUT the help of the booster, and the booster is no longer needed. 

For much more about how boosters work, see our main boosters page.

Why does it matter if your knees bend naturally at the edge of the seat?

Have you ever sat on a really deep sofa? You try to sit all the way back and then you realize your legs are sticking out awkwardly…so you slouch so that your knees bend over the sofa’s edge. Now you’re comfortable! The same thing happens to kids in the car–they slouch in order to be more comfortable. But this is a really big problem, because slouching is VERY dangerous in a car. Boosters give kids a natural edge for the knees to bend over, making it less likely that they’ll want to slouch.

Why is slouching dangerous in a car?

Slouching increases the risk of injury to the brain, spinal cord, and abdominal organs by doing the following: 

1. Slouching makes your seat belt REALLY loose. When you slouch, you introduce slack into the seat belt by lengthening it as you slide down the vehicle seat. There’s also a big gap between your body and the back of the vehicle seat when you slouch. In a crash, this loose seat belt will let your body move much farther forward than it should, increasing the chance that your head hits the seat in front of you. When this happens, it causes brain injuries and also spinal cord injuries because the neck is forced backwards when the head hits. Moral of the story: sit up straight in a car… it’s good for your head!

2. Slouching puts the lap belt across the belly, instead of on the hips where it belongs. During a crash, the lap belt will now pull all the forces of a crash directly across the softest part of your body – your abdominal organs and your lower spinal cord. This is bad news and leads to what is called “seat belt syndrome,” a pattern of injuries to the abdominal organs and spinal cord that can lead to colostomy bags, spleen removal, and paralysis from the waist down. Moral of the story: sit up straight in the car… its good for your belly & spine!

What if your kid slouches in their booster? Isn't a booster supposed to prevent slouching?

Your kid might be slouching because of one or both of the following issues:

The seat pan of their booster is too shallow. When the edge of the booster hits the middle of their thighs rather than their knees, some kids will start to slouch. Solution: Finding a booster with deeper seat pan can help. For high back boosters, the Diono Monterey 4DXT has a very deep seat pan. For backless boosters, the Graco Turbo Go has a very deep seat pan. 

Their legs are dangling. Have you ever sat on a barstool that didn’t have a footrest and realized how uncomfortable it is with your legs hanging? Kids in boosters often experience this and can make themselves less safe by squirming and slouching in an attempt to get comfortable. Solution: Using a footrest can help in this situation. Here’s how to make a safe one at home:

Prevent Slouching with a Homemade Footrest

Try making a homemade footrest using cardboard, bubble wrap, and duct tape. These strong, lightweight materials will make a durable footrest that won’t turn into a dangerous projectile in a crash. Wrap the bubble wrap around the cardboard until it looks like the right height to support your child’s feet when placed in the vehicle’s foot well. Use duct tape to secure the bubble wrap until it’s sturdy. 

My kid needs a booster, but there's no room for one in my car!

Maybe you just haven’t found the right narrow booster… and/or maybe the car seats you’re using need to be narrower to allow a narrow booster to fit next to them. Check out our recommendations for:

My kid doesn't fit in a booster, but still needs one!

You just haven’t found the right booster yet! Check out our page below for suggestions: 

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FTC Disclosure: Affiliate links are included in this page. No monetary compensation was provided, however, a few of the reviewed products were supplied by the manufacturer or distributor to help facilitate the review. All opinions are those of The Car Seat Lady, LLC.