All her letters were cryptically addressed, and never disclosed her father or mum's real name to avoid detection. Her box had her name, Natasha Museveni written in red on a corner on the inside.
Natasha was whisked away from the school one dark night in 1982 after Kenya's security forces learnt that Uganda President Milton Obote's forces were planning to capture her so as to teach the young guerilla leader Museveni a lesson.
But before Muhoozi leads Uganda's forces in redrawing the Kenya and Uganda maps, he will have to consult military records prepared by the second Uganda President Iddi Amin.
In February 1976, Amin held an international press conference and declared that he was going to invade Kenya and restore Uganda's boundary which extended from Lake Victoria up to Naivasha.
He also promised to conduct a referendum in the claimed territories so that the affected people could decide whether they were Ugandans or Kenyans.
His pronouncements caused jitters in Jomo Kenyatta's government because at the time, Kenya had an Army of about 6,500 personnel, Air Force 700, and Navy 350. Kenya had less than 20 armoured vehicles, 14 combat aircraft and four patrol boats.
This made Kenya a sitting duck to Uganda which had a 20,000-strong army and 1,000-man Air Force, 30 Soviet heavy tanks, 100 armoured vehicles and 46 combat aircraft.
Despite Kampala's military superiority, Amin was forced to withdraw and apologise after Kenya deployed a number of tactics, including sabotaging the supply of oil and other strategic goods as well as holding massive demos across the country denouncing the threats.
Amin said he was stating a geographical fact on where the Kenya/Uganda border lay, from a book by a former colonial governor of Uganda. He promised to summarise his new findings in a booklet and send a copy to President Kenyatta.
Although Muhoozi has been stripped of his powers as the commander of the army by his father and the country renounced the general's threat of overrunning Kenya in two weeks on Twitter, it appears Uganda has special attention to Naivasha.
Subscribe to our newsletter and stay updated on the latest developments and special
Pick your favourite topics below for a tailor made homepage just for you