Final answer:
Children's feelings about the painter using their wall, as outlined in the passage, seem to evolve from possibly neutral or accepting to negative as the wall's use leads to destructive thoughts rather than helping them cope emotionally.
Step-by-step explanation:
The question revolves around the evolving perceptions of the children in a passage concerning a painter who uses their wall. Initially, it may be inferred that the children's feelings are negative towards the painter utilizing their wall. As the passage highlights the change from a space designed to help children with their emotions to one that fosters destructive thoughts, it indicates a shift in sentiment from potentially apprehensive or neutral to a more hostile or troubled viewpoint. The children's distress and the context of secrecy and lack of obedience to parental requests suggest a growing discomfort or resistance to the painter's use of their wall.
Without more context, we cannot provide a definitive trajectory of the children's feelings towards the painter's use of the wall. However, it is apparent that the children's initial feelings, possibly of indifference or acceptance, might have transformed into concern or opposition as the consequences of the wall's use became more evident.