What is the significance of the items in Mariam’s tin in the book Shooting Kabul?

The family's unity

Explanation:

The book Shooting Kabul tells the story of an Afghan family trying to escape the country which had been disrupted because of the activities of the Taliban. Fadi was 12 years old, his little sister Mariam was 6. They had an older sister named Noor, and their parents Habib and Zafooni. As they made their way out of the country, Mariam pleaded with Fadi to put his doll in his backpack but he refused, urging her to move along while he held her hand. Mariam's doll eventually fell down and while she tried to pick it up, the Taliban appeared causing the truck driver who was picking them to drive off. Mariam was left behind.

Her tin which was still carried by Fadi who now felt much guilt contained, Mariam's baby tooth,  a tassel from her father's graduation gown, a buckle from Noor's belt, Zafoona's broken pearl earring, and a photograph of Fadi holding Mariam when she was a baby. All these were a symbol of the family's unity.

if its apex this should be the correct answer

war information to be released publicly must first be deemed useless to the enemy