When they were ten, Isaac and Gwen shared a love/hate relationship, which shown they are constantly fighting and arguing with each other. Though in their teenage year now, Gwen and Isaac deeply care about each other. When Isaac went in to the storm with only his SIG suit to bring Gwen out of a storm on Aegis 7. He even rushed her to the surgical pod before the creature incubating in her could kill her just to get out.
It is revealed that they are each other's favorite cousin.
Once Kori joins the crew and notices the closeness she has with Isaac, she has to step in and separate the two on certain moments... like when she's nude and smooshing up to Isaac. Though aside from this, she wants them to be together, since Kori seems to make Isaac very happy.
Crew of the FalconEdit
After realizing of Kori's 'open nature', Gwen has to act as the voice of reason for her. In some situations, she's stunned to say the least that Kori would easily allow herself exposure to others... but mostly to Isaac in particular.