Exposing the current lie about Joseph Smith supposedly getting his theological ideas from his brother Hyrum

A current effort by historians to explain away the Book of Mormon and other theological products of Joseph Smith is the claim that there was supposedly a long period of tutoring that a convalescing-from-leg-surgery Joseph Smith received from his older brother Hyrum, who had been away for a while at a boarding school. Here is the claim:

Hyrum's education at Moor's school provided a tutor for unschooled Joseph. Hyrum's exposure to Dartmouth's theology, cosmology, ancient language studies, architecture, Ethan Smith's son Lyndon, and Solomon Spaulding's nephew James Spaulding from Sharon, Vermont, who was attending the Medical School, all provided discussion material for tutoring Joseph during his long recovery from leg surgery that kept Joseph at home on crutches until the Smith family reached Palmyra. 

https://bhroberts.org/records/rqHlnb-hmznMb/hs_had_access_to_dartmouth_educational_ideas

This morning I was reading from a 1974 reprint (the 12th reprint) of a 1952 book called The Story of Our Church for Young Latter-day Saints, authored by Emma Marr Petersen. The information in it 1) contradicts claims that Joseph Smith had a long convalescence and 2) shows that Joseph would have only been around six or seven years old when he had leg surgery. 

Regarding his convalescence, the book says on page 3:

After the operation, Joseph quickly became well enough to get out of doors. The family thought he would recover much faster if he could go down to the seashore, so they took him to stay for a time with his uncle, Jesse Smith, who lived at Salem, Massachusetts. The sea air was good for him, and it was not long until he was entirely well again.

As to Hyrum tutoring Joseph in the ideas he would later use in allegedly authoring the Book of Mormon, having known many children aged six or seven, I find absurd the idea that young Joseph picked up and retained ideas about "theology, cosmology, ancient language studies, architecture" and so forth at that age. Yet, in "anti-Mormon" circles--where one regularly encounters criticism of the LDS practice of allowing baptism of eight-year-old children who are considered in LDS doctrine to have reached "the age of accountability"--there is an odd willingness to believe that Joseph could have been able and mature enough to internalize his older brother's education. My older brother is really good at statistics; despite talking to him over the years and even taking a college math class with him, I acquired very little from his possession of statistics knowledge.

Below are cropped photos from the history book so people can read for themselves what I have said:

Every generation or two, a new kind of attack is levied on the validity of the Book of Mormon. I think that this latest attack is without merit.