Sheridan was close to her brother, whom she lovingly referred to as "Johnny". He, in turn, referred to her as "Lizzie". She introduced John to her friend Anna, whom he would eventually marry.
In 2257, Sheridan learned that Anna died in a tragic explosion during a short survey mission on the Icarus. During her last communication with her, Anna said that she meant to meet John near Centauri Prime, but got the opportunity to go on the survey mission unexpectedly. She meant to cancel herself, but, instead, John had and got her off the hook.
When John's mission ended in 2259 and he was transferred to Babylon 5, Sheridan traveled to visit him – and to give him the message Anna sent to her two years prior, one that she had held onto since the funeral. She emphasized that he can't blame himself for her having gone on the mission in the first place. She left on the transport, Von Braun.