A Six that only Gaius can see, hear, and feel has been his constant companion almost since the destruction of the colonies. Her exact origin isn't known, but she calls herself an "angel sent by God" to protect and instruct him.
'''President Laura Roslin''': Before the attacks, Laura Roslin was the Secretary of Education for the Twelve Colonies. She'd recently been diagnosed with breast cancer. After the attacks, so many officials had been killed that she held the highest position in the chain of succession, and was sworn in as president. She hid her illness from most people in the fleet, but it got progressively worse, and it had spread too far to be treated even before the attack--until a blood transfusion from a Cylon-human hybrid apparently cured her. She had a relapse, but survived this as well.
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