Mom Snapped When I Gave My Sister Cough Syrup

Mom and Dad keep claiming that I'm their firstborn, so they need to love me with all their hearts. Already, they're saving up for my college funds and keep taking me on vacations abroad just to explore the world. This time, I've gotten a full score on my exams. My parents decide to take me and my four-year-old sister, Amelia Orson, on a trip. Worried that I might mind Amelia's presence, they even specifically explain to me that no one is capable of taking care of Amelia in their stead, so she has to come along. I accept the explanation immediately. But Amelia falls sick right before the trip. There isn't any cough syrup left at home, so I use my pocket money to buy some imported cough syrup and feed Amelia with it. I thought I'd get praised for my efforts. Instead, Mom rushes over to induce vomiting for Amelia. With red-rimmed eyes, she scolds me, "How dare you feed her medicine without checking the source! Do you have any idea how lethal that is? When I was young, I almost died from a dose of misused medication fed by my own sister! How dare you try to harm Amelia, you wretched child!" After that, Mom tells Dad to bring out his suitcase so that she can lock me up in it. "You want to go on a trip because you've scored full marks in your exams, right? Fine! Have all the fun you want in the suitcase!" What they've forgotten is the fact that Dad often uses this suitcase on his business trips, so there's a TSA-approved lock on it. I can't even open the suitcase from inside.