MIL is saying she doesn't want to buy a car seat for DD because she'll be out of it by 2 years old and into a booster. Is this true??? I really have no idea what a 80lb child (weight limit on front facing) is age wise but I thought she'd be in this until 3. You mom's of toddlers how long did they REALLY stay in car seat??
THANKS A BUNCH!!

Re: How long in Car seat??
Kristen (7), Timothy (5), Robert (3), Charles (9 months)
Thomas ~ 07/07/2008 ~ 8 lbs, 5 oz
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Global Developmental Delay consisting of a receptive language delay and self help skills delay
Just buy a car seat for her then.
Kids are in carseats (usually by law) WAY longer than they used to be. And it's best if they are in them up through the height/weight limit, even if that means they are significantly older.
The bare minimum to be out of a harnessed seat and in a booster is age 4 AND 40 lbs. However, most kids are not ready (developmentally) to be in a booster before age 5-6. They MUST sit correctly in the seatbelt (no slouching, leaning to reach anything, putting the shoulder strap behind them) 100% of the time. Also, kids who tend to fall asleep in the car are generally not ready. The position they are in while sleeping is not safe. We are just now booster training my 6 year old DSS.
Also, smaller kids are at a huge risk for "submarining" under the seat belt in a crash. Essentially, slipping under the seat belt and out of their booster. Please google Kyle David Miller Foundation. They will have tons of reasons why extended harnessing is infinitely safer.