'too big' for HBB at 6 years old?

[devon]

My friend recently went to a local firestation (local to her) to have them help reinstall her son's seat to RF (since he is not yet 2) - which is GREAT!  The person there is supposedly NHTSB carseat certified.

Her son is 6.5 and in kindergarten.  The person told her that she needed to move him from his Graco Turbobooster HBB into the LBB of the seat, because of where his knees were on the booster.  Something about him fitting better and safer in it without the back on.  I had never heard of such a thing!  My 6.5 year old son just moved into the HBB part of his Nautilus because he had outgrown the harness height wise (he is about 60 lbs and 52'' tall) - her son is a fair bit smaller then mine.  It is making me wonder what the heck?  I couldn't imagine him sitting in a LBB - it freaks me out to see him in a HBB!

What is the deal with knees and the booster seat fit?

TIA!

Devon

[DahliaRW]

If the shoulder guide is below his shoulder the high back portion is outgrown.  If not it still fits.  And a 6.5 yo is perfectly safe in a hbb, why would that freak you out?  He's safe in a lbb too, it just may be less ideal.

[an_aurora]

The knees would be just the same in the LBB as the HBB.  Which is to say, he's fine in a HBB as long as he fits torso-wise with the shoulder guide above the shoudler.