Protesters have faced beatings and arrests.
Judge Richard Twomlow sentenced Edwards to six years imprisonment and Sansom was jailed for six years and three months.
Danny Fenster was detained at Yangon International Airport as he was about to board a flight to the United States.
The defendants, Levi Edwards and Morgan Sansom, have never shown any remorse for killing our mother.
State Department did not immediately comment on the trip.
The United States suspended a trade deal with Myanmar until a democratic government is restored in the Southeast Asian country.