Question: are nebula and ronan related?
Answer: Nebula is a former Luphomoid assassin, an adopted daughter of the intergalactic warlord Thanos and adopted sister of Gamora. As the right-hand woman of Ronan the Accuser during his and Thanos' quest to retrieve the Orb, she helped him fight the Guardians of the Galaxy during the Battle of Xandar.