Because this is getting too big to keep sane in a Notepad document.
Haruka's personal timeline during the story.
Haruka Nanase is born to a pure-blood wizarding family in a wizarding village. From the moment he's born, he displays an affinity for magic bursts.
Shortly before his 4th birthday, Haru's parents leave him unannounced in the care of his grandmother in a different magical village (perhaps Iwatobi). This causes development of abandonment issues in Haruka and difficulty trusting others.
The affinity he showed at birth manifests in a natural ability to use nonverbal magic, so his grandmother spends these years both raising him as well as fostering his magical abilities, teaching him simple spells and tutoring him about magic. The spells he learns from her are able to be used nonverbally by him really quickly due to his affinity for it. She also gives him some broom flying lessons in their backyard.
Although it's a couple of years early, his grandma decides to get Haru the pet that will accompany him to Mahoutokoro. On his birthday, they take a trip to the nearby magical pet shop where Haru finds a domesticated Fuuri.
Deciding on that pet, his grandma buys the Fuuri for him and he names it Sora, giving it the same name trait as his own, since it's a male Fuuri.
When he's 9 years old, his grandma passes away unexpectedly in her sleep. Haru is very shaken by this, but soldiers on despite the depression it causes him. Having no other guardians, he's taken to live with his parents for the remainder of his time before formal schooling, though he rarely sees his parents due to their line of work.
A few months before he turns 11, Haru receives his long-awaited invitation to the school and prepares to go, leaving by train to head for the town the school is near when the school start date draws near.
Events that happened to or were witnessed by Makoto.
Makoto is born a half-blood wizard to his pureblood mother and muggle father in the muggle village that the train to Mahoutokoro usually stops by.
Ren and Ran are born when Makoto is 5 years old.
Makoto is taken by his mother to a wizarding pet shop where he meets the kind old shop keeper. There, he gets his first pet, two flying seahorses. He obtains them during the winter when he's 6 and takes care of them through the year he turns 7 (2003). Shortly before the new year, his flying seahorses fall ill.
Though he did his best to care for his flying seahorses, they only continued to get more and more sick until his mom had to call the old man and ask him to make a special house call to check on the fish personally.
Unbeknownst to them, a powerful typhoon (Typhoon Dianmu) was approaching. It hit their area around the time the old man was to be on his way. Though they hoped he'd decided not to come given the sudden weather, he still tried to get there but ultimately died in the storm, due to the ferocious winds and rainfall of the typhoon.
Because the old man wasn't able to make it, Makoto's flying seahorses subsequently died a few days later. He's 7 years old at the time.
Due to living in a disguised magical house in a muggle village, Makoto is able to attend public school in the muggle world until he comes of age to go to Mahoutokoro.
During this time, he makes a friend out of Zaki-chan at school and knows her for quite some years. But during the year when he's 10 years old, Zaki suddenly and unexpectedly kills herself by jumping from the school roof. This is his second traumatic incident involving heights and/or flying. He's 10 at the time of this.
Although he'd just turned 10, Makoto also receives his invite a few months before the start of the school year when he would turn 11.
Rin Matsuoka is born to pureblood wizards in the castle town for Mahoutokoro.
Kou Matsuoka is born, a year younger than her brother.
Rin's dad dies in an unknown accident a few months after he turns 5. At this time, Haru and Makoto are 6 years old.
Rin also receives his invite, despite being 9 at the time of its arrival.
Nagisa is born to a mostly pureblood family, though he specifically is born a Metamorphmagus. He's the only one in his immediate family to have inherited the recessive trait.
Rei is born to muggle parents in a muggle village.