Shara Bey is a human A-wing pilot of the Rebel Alliance's Green Squadron, wife of the commando Kes Dameron, and mother of Poe Dameron. She first appears in Greg Rucka and Marco Checchetto's Star Wars: Shattered Empire #1 (Marvel, 2015).
The four-issue answer to "what happened next"
Shattered Empire was the first canon story set after Return of the Jedi, and it follows Shara through the immediate aftermath of Endor. She flies in the battle itself, then takes a series of missions in the collapsing Empire's wake — including one flying Leia Organa to Naboo, and one impersonating an Imperial pilot to help Luke Skywalker recover two Force-sensitive trees from an Imperial research facility.
The tree
Luke gives her one of them. She and Kes plant it at their home on Yavin 4 when they leave the war, and it is the detail that quietly connects Poe's childhood to the Jedi. It is a small, well-judged piece of continuity work — the sort of thing tie-in comics do better than films.
Why she is in the encyclopedia
Because Poe Dameron's competence needed an explanation and this is it: he was raised by a decorated combat pilot who taught him to fly before he could reasonably be trusted with it. She is dead by the time of the sequel trilogy.