I think this is the most endearing note I've ever read, despite the child's indignation. If you've never perused Passive Aggressive Notes I suggest you take a break for some hilariously written indirect resistance.
'Emily says her parents in Massachusetts recently dug out this note from the family archives, written when Emily was six. (She’s now a high school English teacher.) "None of us have any recollection of the circumstances surrounding it,” Emily says, “but my mother must have done something pretty awful to warrant such a melodramatic note, my six-year-old rage boiling just below the surface.” '