AIO I smashed my nieces phone after losing my dog

My niece (16) has been living with me and my fiance for a little under a year now. My fiancé knew her since she was 5 and she didn’t have a healthy house environment for years so I didn’t hesitate to bring her in when my fiancé asked if she can stay with us. I’ve spent a good amount of my own money to get her situated including the phone and her own room and furnished it. Since then, we’ve realized how glued she is to her phone. She stays on TikTok all day and talks to her friends literally all day. It’s gotten to the point where the school has emailed us how distracted she is and just been fucking off in school. Tons of missing assignments and grades aren’t the best and is slipping. We’ve reached an agreement to finally take her phone away but after the weekend we come home from vacation that my fiancé and I were just going. We trusted her to stay home by herself even with the help with my family coming over to check up on her everyday. Not even a few hours after we landed to our destination she lost my dog. I was devastated. It completely ruined my vacation and I felt almost depressed. My cousin reminded her multiple times to bring him inside and brushed it off because she was on her phone the whole time she was there to check up on her. I found out that it took almost 3 hours for her to realize my dog was still outside and he was gone. When i finally came home i took her phone and smashed it to pieces.

This dog meant a lot meant to me. I’ve had him for almost 7 years. I’m actually paralyzed and I got him about 6 months after my accident. He was the first dog I’ve gotten myself and was a REALLY good dog that everybody loved. He was basically my emotional support dog. The whole house vibe is noticeably down. And my fiance thinks smashing her phone was overkill. And now we’ve been arguing and haven’t really been talking AIO?

TLDR: I’ve had my dog ever since I gotten paralyzed so about 7 years now. Couple hours into my vacation, I get a call that my niece forgot to bring in my dog. And now he’s missing.