NostAlgic/theories

Mother A Suffers from Drug Addiction
It looks like A's mother is taking drugs (as shown in Ending 1) that make her aggressive and tough enough that she can easily kill her child. Based on the interactivity of the Sugar Sea World, the first dose was taken at one of the parties, what could guess or was notified A.

A's Heaven and Reunion With Their Mother
This theory is inspired heavily by noildoof. There is Christian symbolism like crosses or references to angels that are seen in A's dreams. Their dreams are much more likely to be their Heaven, made from their memories. It is very likely they are religious, and A may not even be dreaming at all, they might be dead. The dark parts of A's dreams (ex. The room where you find the Carnation effect is A's fears of their mother when she got high on drugs. With this in consideration it could be interpreted that A died by the start of the game, and they are waiting for their mother to join them in Heaven. Even though they feared her darker side, A still loves her and wants to see her again in Heaven. In the most recent version (Ver. 0.08), there is only the bad ending, which very likely could be A revisting the memory of how they died. In ver. 0.07, there is a good ending that could be interpreted as A's mother dying from drug overdose, and that waking her up means she can finally meet up with her child. Her ending quote "Good Morning Allan" likely means that A and their mother finally is with A and they are in Heaven together, finally able to rest in peace.