Which measurement to use height/length?


Well-known member
My daughter is tiny at 3y4m. Her standing height is 86cm or nearly 34". When measured lying down/recumbent, it's about 4cm/1.5" longer (35.5"). (Her weight is 25lbs.)

I'm asking because we have a trip coming up in a couple months. It's conceivable she could grow a half inch and thus max out her travel seat for RF (Cosco Scenera) if I take the latter measurement, but if the other measurement is more accurate, there's no way she'll outgrow RF before then.

I know it's a large discrepancy, but when I measure her against the wall at home, I also get nearly 34". (There was also an inch and a half difference in the measurements a year ago, so at least it's consistent.) I'm also awaiting results of a bone age scan which will help me decide whether FF is even an option in a pinch (rental company gives us a sub-compact instead of a full-size sedan, etc).



Well-known member
I'd use the height standing up. Once kids are past about age 2, that's how doctors measure and I would assume that car seat manufacturers would use the normal way of measuring as a guide.

If she is still within the shell, then I'd definitely use the standing measurement.

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Well-known member
She's got lots of shell left, as is typical with my kids. They outgrow by standing height limits before the shell height rules or weight.

Thank you.

I suspect the doctor's office is measuring both to show growth from year to year. She only grew an inch and a half in the last year by my reckoning, so the doctor didn't like seeing 34" (lying down 2014, I suspect nurse thought she was much younger) with 34" (standing) this year.

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