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.
Dad Character Timeline in Turtles All the Way Down
The timeline below shows where the character Dad appears in Turtles All the Way Down. The colored dots and icons indicate which themes are associated with that appearance.
...spends much of her morning procrastinating about texting Davis. She remembers that right after her dad died, she could still think of him as though he were real. Gradually, it became... (full context)