Via explains that she always knew August didn't look normal, but she never used to see him the way that others see him. However, when she was eleven, she went to stay with Grans for four weeks while August had his jaw surgery. It was the first time that Via had been away from August for so long, and it was amazing to suddenly not be stared at in public.
Via's experience at Grans' house illustrates how bound up Via is in August's identity. The month at Grans' house also seems to be the first time that Via is cared for like a child since August's birth, which presumably showed her that she does need care.
Via says that Grans was the kind of grandma who did everything with her grandkids. That month with Grans was possibly the best time of Via's life, and returning home was hard. Via remembers seeing August running downstairs to meet her and seeing for just a second what other people see when they look at August. It was over in a second, but after that point, Via always saw two Augusts: one she sees blindly, and one that other people see. Via never told anyone about it, even though she planned to tell Grans about it at Thanksgiving. However, Grans died suddenly two months later of a heart attack.
When Via says that the time with Grans was the best time of her life, it emphasizes that children need true guardians in their lives, even if said children already seem mature and independent. Her return represents an unfortunate coming of age moment for Via, as she has a very adult realization about how August appears to others. Widening her understanding will allow her to better empathize with other people.
On Via and Grans' last day together, they watched the sunset together. Grans had told Via a secret: she loved Via more than anyone else, even August. She explained that August had enough angels looking out for him, but nobody was looking out for Via. Now, Via hangs onto Grans' secret and feels that it's like a blanket.
Grans' words show that she's aware of the lopsided dynamic at work in Via's house, and she also understands that Via needs to be cared for just like any other child. Grans also implies that August has a huge support network, which will in turn help him get through life even when it’s difficult.