Deeply concerned about the welfare of others, including her brother. She seemingly has a strong moral sense happy to help in the reconstruction of the boardwalk but nothing that could be considered to be directly aiding a villain like Skitter.
While the rest of her family was in the hospital due to toxic mold exposure, Merchants attacked the church she was staying at with her younger brother and took him with them. After Skitter's speech declaring the Boardwalk her territory, Battery left before she could ask for her help. Skitter agreed to bring her brother back.
She starts working for Skitter in exchange for Tattletale taking care of Bryce and working on rehabilitating him. Her first job had her going out with Charlotte and checking on the people in Skitter's territory.
Letting the new 'warlord' know about a rat infestation.
↑Sierra Kiley – Skitter’s ex-second in command. A college student with long red dreadlocks, Sierra joined Skitter and soon became her second in command, after Skitter rescued her brother Bryce Kiley from the Merchants (it was found that he’d joined the group). Left Skitter’s forces due to moral concerns. - Cast (In Depth)
↑How was Sierra managing as a corporate magnate and front-man for a villainous organization? - Excerpt from Scarab 25.3
↑Others. A red haired girl in another world, shouting to people as she ordered them through a building project, a girl who was standing outside in the rain, in another world, kids peering through the window behind her. - Excerpt from Speck 30.7
↑Sierra Kiley, Relay communicated. Board member of Rock Bay Reconstruction Group. That’s one of the biggest construction firms, with its roots in Brockton Bay. She’s a candidate for mayor of the Megalopolis, but she’s not expected to win. Foresight thinks she has her hat in the ring for other reasons. Access, possibly. We know she has ties to organized crime, if you couldn’t guess from her background in Brockton Bay. She doesn’t necessarily know we know. - Excerpt from Interlude 2 II