anonymisss, I had no clue where you were going when you just mentioned your sister. Is she still in school?
Advice: (disclaimer, I have never had any need to use this advice, I’m not guaranteeing it will accomplish anything) Buy her a small present with a card for her b-day (or if shes 18 than graduation) and do something with her, maybe go out for ice cream or something just because your sisters and you wanna have a better relationship with her than you do now. When you see her ask her how her day was, ask her advice about any issue (problem students?) ask her help planning an end of the year celebration for your class, game, party etc. (I hope I’m remembering correctly that you teach) Talk about her talents, say loud when she can hear, maybe sara rivka rachel leah would know, have <whatever>
Now that we just went through all that, what caused her to go off?
I did have her in mind during davening today, (and you that you make it through in one piece)
🙂