As the team is setting up for a match, a friendly Ana and Pharah might trigger a new interaction. Pharah asks her mother if she thinks it's time Sam, Pharah's father, knew Ana was alive. "You let me worry about what your father needs to know," Ana said.
Although this bit of information mostly informs fans that Sam is unaware Ana survived her duel with Widowmaker and is operating under the name Shrike, it might be a subtle way to express Ana's guilt.
During a mission to free Overwatch scientists held hostage by Talon, Ana was presumed dead after being shot in her cybernetic eye by Widowmaker -- who Ana recognized to be Amélie Lacroix, wife of Overwatch operative Gerard Lacroix. Based from the timeline of events, her presumed death must have happened six years ago (in the Overwatch universe). She spent a lot of time alone, recovering from her battle, and went under another name completely, keeping Ana Amari dead -- and six years is a long time to be dead.
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Pharah is seen visiting her father in the Reflections comic, which suggests they have a good relationship and spend time together. The relationship between Ana and Sam is not explicitly described in Overwatch, but an in-game spray of the family shows he was a part of their life. He must have loved Ana and her "death" must have been a painful experience for him. Sam had to make peace with it, however.
He lives in a world where Ana Amari is dead, so for Ana to resurface relatively unharmed would mean his entire world would change.
Pharah only knows Ana is alive because of a letter, but Sam doesn't know anything. At this point, Ana might not be inclined to tell Sam she is alive because of guilt. Her "death" caused him pain and he had to deal with it while taking care of Pharah and possibly helping her deal with her own grief. Sam might have taken on the burden of parenting alone while Ana was involved with Overwatch during the Omnic Crisis, and now he had to take care of raising Pharah alone as Ana is believed to be dead.
Ana might not be ready to tell Sam she is still alive. She might feel guilty for leaving him alone with raising Pharah and choosing not to tell him about being safe.
Updates to the Anubis map raised speculations that lore for the mother-daughter duo might be on its way. Although voice line interactions aren't as satisfying as an animated short or comic, it might be a small appetizer of what's to come.