Dad is Aza's father, who died of (presumably) a heart attack while mowing the lawn about eight years prior to the start of the novel. Mom describes her husband as "a worrier" like Aza, and thinks that he would've understood Aza's anxiety better than she does. He enjoyed taking cell phone photos of the sky through tree branches, and Aza keeps his phone in working order so she can revisit the photographs on the phone. Aza's car, Harold, also belonged to Dad.