Grew up on Corellia, joining the Imperial Academy to become a pilot like his father.  But when his father was killed the exact cause was hidden up and Elam started to question the Imperial propaganda. 

Leaving Corellia Elam soon found himself as a starfighter pilot for the Rebel Alliance, but still seeks the truth about his father.

Spanners always had a knack for technology and from a young age was always bound to become a tech or mechanic.  Spanners family however were proud member of the Rodian Hunters Guild and frowned on his career choice. 

Tired of his families bullying Spanners left Rodia only to find more bullying, this time from the Empire.  Eventually Spanners joined up with the Rebel Alliance who appreciate his skills more than anyone has done before.

R4-G1

Astromech Droid

R4 has been found himself around Rebel bases since the formation of the Rebel Alliance after the Clone Wars.

Exactly how old R4 is is unknown, and he's not beeping.  R4 is certainly a lot older than some would believe.  He was present throughout the Clone Wars and very likely from a long time before that.