If it is true that a child comes equipped with his or her own innate timetable for mental growth, one can conclude that?

Question

(1) siblings must have the same timetables
(2) the timetable should be affected by the child‟s diet
(3) you cannot teach a child mathematics until a specific time in his or her development
(4) it would generally take more time to learn a very simple language than a complex
language
(5) the child would have to learn language in order to reason