Answer: That he is slowly moving away from his mom and that their relationship is slowly fading.
Explanation: We see that in the bus scene, Bao gets frustrated and upset because his mom didn't let him hang out with the kids. This happened many times throughout the story and is the reason for their realationship's downfall. Later we get a glimpse of the room and it appears that he's made some new freinds. He then goes into the car leaving his mother alone to eat all the food herself.
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