Vera Briggs is the wife of Jackson "Jax" Briggs and mother of their daughter, Jacqui; they met while Jax was in recovery after his time as a revenant. Vera is close friends with Jax's former Special Forces partner, Sonya Blade and is aware of her husband's involvement in the protection of Earthrealm.
Mortal Kombat X Comic Series
Vera called her daughter Jacqui again, expressing her concern over having not heard from her daughter in several days when her husband Jax was thrown through a nearby window. Vera quickly ran to his side, and when Jax told her to run, Vera refused, even as the Outworlder Reiko made his way through the wall of their home. Reiko quickly incapacitated Jax, demanding the Kamidogu dagger that Raiden had entrusted him.
Jax refused, so Reiko snatched Vera by her throat and held her aloft in the air, giving Jax the ultimatum of his family for the dagger. Jax complied and Reiko left with the dagger.
Vera greeted the thunder god Raiden when he arrived at the Briggs' farm, explaining to him Reiko's attack, before demanding that Raiden get Jacqui back, seeing him responsible for Reiko's attack as he had given Jax the dagger.
When Jacqui was finally returned to the Briggs family farm, Jax was at first inclined to never let her leave home again, but it is Vera who convinces him to teach her to defend herself. Vera was present and overjoyed to be reunited with her daughter.
Mortal Kombat X
Though unseen, Vera is mentioned during Jax and Sonya's conversation when she comes to recruit for a mission to the Netherrealm. She is also mentioned in several intro dialogues between Jax and Jacqui.
Mortal Kombat 11
In-between the events of the previous game, Vera died of unknown causes, which instigated Jax's honorable discharge from Special Forces. She is also mentioned in an intro dialogue between Jacqui Briggs and Noob Saibot, in which it is stated that Noob has her soul, although this hasn't been confirmed.