The law is clear about young kids using a car seat or booster seat, but it can get confusing for parents when it comes to the actual requirements. There are so many car seats out there all with different instructions, but the law remains the same.

Every week, Dr. Shawna Murphy, with Lehigh Valley Health Network, treats several children injured in car accidents. That's why Murphy said it's important to know which car seat is appropriate for your child.

"The regulations are rear seating for up to two years unless they hit the max weight of the seat, and then front seating," said Murphy.

69 News editor Jen Dilliard's daughter, Maddie, is 4-and-a-half-years-old and 43 pounds, so Maddie rides in a forward-facing seat.

"I have no clue how long we are going to have to use it," said Dilliard.

"From zero to age 4, they should be in an approved car seat, usually rear-facing to forward facing. From 4 to 8, they should be in an approved booster seat," said Tpr. Mark Allen, Pa. State Police. "The weight would be 40 pounds and 4-years-old all they way up to 100 pounds and 8-years-old."

It's strongly advised that children not sit in the front seat until the age of 13 because of dangers associated with airbag deployment during an accident.

Now that you know the federal requirements, you also need to know about registration.

Each child seat should be registered. If you haven't done so, just look for the serial number on the bottom of the seat and visit the manufacturer's web site.

Each manufacturer is required by law to notify consumers of recalls.

While you are looking for the serial number also check for a expiration date. Car seats have a life of six years and should be destroyed afterward to ensure they don't fail when you need them the most.

"Because of the weather and the materials, stress fractures that may not be visible to the eye, and they are only made to last so long," said Allen.

Experts said it's not a good idea to buy a used car seat because you don't know its history. It might have been involved in an accident, which could impair its ability to protect your child.