AITA for revealing who paid after my sister mocked my child at her engagement brunch?

At my sister’s engagement brunch, she raised her mimosa and said, “Some women teach us what happens when you lower your standards.” My mother laughed. My father joined the toast. Then my 8-year-old whispered, “Mom, am I your bad choice?” I stood, placed an envelope next to the cake, and said, “Then let’s discuss who paid for this room.” ---------------🦦Otter Stories🦦--------------- #reddit #stories #redditstories