you know, Ruthie had a blood curdling scream back in the day in her infant bucket.
And I grant you, it made it harder to drive. A switch to a good convertible seat (40lb limit Triumph... but hey, it fit and she was all of a sudden silent) cured that...
We heard it again when she was almost 1yr old... from her legs... her pigeon-toeing stemmed from her hips and pressing her feet into the vehicle seat caused real pain... and she wasn't old enough to keep her legs bent (especially with such short legs).
While it did make me have to think about turning her ff at 1yr old (note... did not do it... forever thanking murphydog for that one... she searched and found me the solution of reclining the captain's chair of my still very new at the time van)... never in my wildest dreams would I turn her before that.
I honestly would have gotten those ear plugs that muffle noise but don't keep you from hearing the important noises (sirens and such) or (and this sounds just as bad or worse than ear plugs) I would have moved her to the third row (which I ended up doing anyway, when she was older and used the scenera full time with Jeffrey in the Marathon... so I could more easily buckle all 3 kids) so that the noise would not be as loud.
I would stop approaching it from the safety aspect and instead look at it from a compassionate understanding aspect.
Offer to help her make him more comfortable and happy rearfacing.... so that he can stay rearfacing to the minimum requirements of his seat at least (1yr, 22lbs, 34")
My guess is the seat needs a better recline and/or he may have the same leg issues Ruthie had... OR... it could be something as silly as he's crying because his pacifier dropped and she wants him facing forward so she can reach back while driving and pop it in his mouth.
Of course, there is also a possibility he has reflux and needs LESS recline.
I guess my point is... before jumping onto the safety stuff, I'd be asking why he's crying so badly that she feels she has to flip him before it's safe.