Make her cry

昨天晚上女兒很得意地跟我說："Mommy， 我忘了告訴你， 我昨天（4月1日）差點make my best friend crying"。 我說：“how?”。 她說：“I told her that I'm not going to sit with her anymore (on bus)". she almost cried and asked :"why?" I said: "happy April 1st!". wow, I said:"你小小年紀就會把自己的快樂建立在別人的痛苦之上，Good!" what does that mean? she asked? "that means forget about it", I said.