The Weskers' Biography.

After the Investigation

After the investigation ended, the Weskers had no adult family left, and they lived with their older sister, Jane S. Hallo
During this time period, the Weskers had learned how to fight and defend properly, set traps, etc.
It was also during this time period that Jane was killed as 'misheard target information' by a gov't counter-sniper.
The sniper was relieved of duty, and later performed a heist with a local criminal gang, by the time this happened Lupus D. Wesker was 17, he had tracked them back to their hideout, and, without using a lethal weapon, took them down.
Vasya D. Wesker, however, was 14 at the time.