Cecily Aguilar admitted to helping her boyfriend, Specialist Aaron Robinson, dismember and dispose of Guillen's body near the Leon River in 2020.
Today would have been Vanessa's 21st birthday.
Legislators on Capitol Hill Wednesday held signs that said "Military sexual trauma ends with us" as they presented the legislation.
Two subcommittees will look at whether there are "deficiencies" in the chain of command that led to those deaths this year.
The family of the murdered Texas soldier, who had levied harassment allegations, said the change doesn't address accountability issues.
Sgt. Elder Fernandes vanished earlier this month, continuing a string of disappearances of soldiers from the Army's third largest post.
