What does sal notice about phoebe's parents that reminds her of the pickfords her mother's parents?

Sal notices that Phoebe's parents exhibit a similar dynamic to that of her own grandparents, the Pickfords. Both sets of parents seem to have a strained relationship marked by misunderstandings and unspoken tensions. This resemblance evokes feelings of nostalgia and reflection in Sal, as she contemplates her own family's complexities and the patterns that may repeat across generations.