Do you have a citation that it was "normal"? Or if it was 'normal' was it because of forced arrangements like the FLDS do? BTW, Joseph Smith married Helen Mar Kimball in May 1843. He was 37 and she was 14. This is not normal by any standard of the century, he was more than old enough to be her father and already had multiple other wives at the time.
lady lawyer was inaccurate, or possibly misrepresented, in regard to the median age of marriage in the 1800's.
The median age was above 20. This is, obviously, much higher than the 14 year old, Helen Mar Kimball.