To expand the discussion.....
When I studied nutrition and feeding livestock, many tables were provided specifying the range of nutrients fed on a daily bases for optimal growth, by expected adult size.

When visiting a farm that raised a work horse, the Belgium, the feeding regime was much different than what I encountered years later at a barn feeding future Thoroughbred race horses. Different body structures, different maturity age, different feeding regime.

A point of interest, the TB foals , one year of weanlings, all developed epiphicitis. Their joints were enlarged and painful. All growing too fast. The amount of feed specifically grain was pushing these babies faster than was a healthy rate.

Do we see this in humans??? Im honestly curious about the balance of proteins to calories in our children.

My 2 children are very different. One with a BMI of 17.8 and other is 21...... each built very different.

One like an Arab horse, sort of.
One a TB.
And me-- a Belgium.

How to meet the optimal needs nutritionally? Pediatritians follow a growth chart, a sharp up or sharp down is a heads up to look for a problem...... but little to no info on the feeding of children.

Feeding the adult body is easier.