Jack Fawcett

Jack Fawcett is a real-life person who's fictional documents can be found in Shadow of the Tomb Raider.

Real History
Jack Fawcett is famous for being on his father's, Percy Harrison Fawcett, expedition to find the Lost City of Z in the jungles of Brazil, along with his friend Raleigh Rimmel. They traveled towards the Amazon river, where they went missing, presumed to be killed by the natives. Their last known location was near the Xingu River.

Shadow of the Tomb Raider
Jack Fawcett set out for the expedition to find the Lost City of Z in 20th April, 1925 with his father Percy Harrison Fawcett, and best friend Raleigh Rimmel. He wrote several entries to his journal documenting their travel. On the 18th July, Jack's best friend, Raleigh died. Jack and Percy continued their travels. By August they ran out of food, and lived off of the jungle. In 9th August, 1925, Jack summarized his travels in his journal, he noted the deaths of his friend and father, and his determination to find Z. Jack Fawcett managed to reach the outskirts of Paititi, what he believed to be the Lost City of Z they set out to find.

Since the expedition took place in 1925, it can be summaries that Jack Fawcett has passed by the time Lara Croft finds his journal entries in 2018.

Trivia

 * Percy Fawcett gifted a sextant to Jack Fawcett.