The killing happened on Feb. 14 at about 9:30 p.m. when Tony Earls and his wife drove to an ATM to deposit some cash and a check, according to the district attorney’s office. A man then ran up and put a gun in the wife’s face and demanded their money, car keys and purse, the district attorney’s office said. The couple initially complied with the robber, handing over the check, cash and wallet, before the robber took off running, the office said. Earls, who got out of the vehicle, said he heard gunshots and thought he was being shot, so he shot the robber, the office said. But he ended up hitting a truck that happened to be passing at the same time, killing 9-year-old Arlene Alvarez in the back seat, the district attorney’s office said. The girl’s parents, Armando and Gwen Alvarez, told CNN affiliate KHOU in February that the family was driving to a Houston restaurant for Valentine’s Day dinner when Arlene was shot in the head. “I pulled over immediately, got her out of the vehicle,” Armando Alvarez said. “I hope no one ever has to go through this.” The robbery suspect, who remains at large, will face felony murder charges in the killing, Ogg said. A $30,000 reward is being offered for information leading to his arrest. “We will focus on apprehending the robbery suspect who started this chain of events,” he said. “I know we can find this killer with your help. Someone knows who he is.” Arlene’s aunt, April Aguirre, lamented the lack of charges at a joint news conference with Ogg on Tuesday. “I wish it was Tony Earls who was found guilty, but I know the decision is final with the grand jury,” he said. “I pray that we can find this person and bring them to justice, because Arlene didn’t want to die. She didn’t want to die on Monday night, on the way to dinner.” He called on the public to hand in the robbery suspect. “I want someone to be held accountable, because this family should not continue to suffer like this. This is unexplainable pain,” she said. “Gwen and Armando and the rest of the Alvarez family deserve to have their baby girl. She didn’t deserve this ending.” The Earls’ attorneys, Brennen Dunn and Myrecia Donaldson, said in a statement to CNN that they were pleased with the jury’s decision. “We would first like to extend our condolences to the Alvarez family once again. There is no greater loss than that of a loved one and we continue to mourn the loss of such a beautiful soul,” Dunn and Donaldson said. “We are relieved that, despite the emotion and tough decisions that had to be made in dealing with this case, justice was served for Mr. Earls. We do not envy the grand jury’s difficult task, but we certainly appreciate their careful deliberation,” they said. “We support the Alvarez family as the search for justice for Arlene Alvarez continues. Mr. Earls stands ready to assist authorities in any way he can to bring those responsible to justice.” CNN’s Eric Levenson contributed to this report.