August's eyes are almost halfway down his cheeks and slant at an extreme angle. They bulge and his eyelids droop, and he doesn't have eyebrows or eyelashes. His nose is fleshy and seems too big, and his head looks like it's been pinched at ear level. August has no cheekbones but deep creases on either side of his mouth. He's had a few surgeries to correct his mouth, but his teeth still splay out and he has a severe overbite. He only has a chin because of a surgery to put part of his hipbone where his chin should be, and now he can keep his tongue in his mouth, talk, and eat. He can hear too, which is unusual for kids with birth defects like this.
By telling the reader what August's face looks like, Via challenges the reader to "choose kind" and continue to see August as a child worthy of love, care, and respect. August made sure the reader sympathized with him by focusing on his inner world, while Via presents more of a challenge by putting the reader in a position closer to the strangers that are afraid of him.
Eventually, August will need hearing aids, which he hates the idea of. Via wonders if August knows that wearing hearing aids will be the least of his problems. She wonders if he understands how others see him, or if he's just so good at pretending that he doesn't notice his face anymore. Via wishes she could ask him these questions. She explains that she could read his face better before his surgeries, but now, it's gotten more difficult. Mom and Dad can still read him, but Via can't. She thinks that he's ten years old and can use his words like anyone else; it's time to stop treating him like the sun and make him grow up.
If August were to rely less heavily on his parents for care and affection, it would perhaps allow Via to receive more attention (given her belief that there's a finite amount of love to go around). Regardless, she is clearly aware that August is in a difficult spot developmentally and is in between child and adult. The fact that Via struggles to read August's face suggests that she's also starting to pull away from her role as a caregiver for him.