AITA for taking my daughter home after I found out my parents let her get a loan to pay for my mother's birthday party?

I (M/40) have one sister (F/42) and my parents are in their 60's. I have 2 kids (F/19 & M/17).<br><br>My mom's birthday was last week and my parents wanted us to celebrate with a party. My sister and her husband took care of decorating and catering. I was to pay for the venue and I happily agreed. It cost me about $1,400 to book the place. <br><br>Only 20 people were invited and we had a great time and my mom even started to cry seeing "how much her family loves her to organize this beautiful celebration". <br><br>On the way home I asked my daughter if she enjoyed herself. She said that she did but, in all honesty, she wished that her grand-mother "had opted for something more lowkey to celebrate because she didn't really like birthdays to be a big deal". <br><br>I asked her "Why didn't she say so? I would've gladly given her the $1,400 I paid for the venue to just have a quiet dinner or something and save us all the hassle and the money". She didn't answer. <br><br>I insisted and she told me that what I paid for the venue was nothing compared to what she paid. I was perplexed. I asked her what did she mean and she finally confessed that after my parents got wind of my arrangement with my sister, she was pulled aside by them and they asked her to pay for the food and the decorations. I asked her how much she paid and she said that she gave them $6,000 and that she had taken a loan for it. I was flabbergasted. I asked her why she didn't say anything to me and she told me that she didn't want to disappoint her grandparents and that they told her not to tell me and that they'd take care of paying her back. <br><br>I felt a strong angers and told her to get in the car. We both went home. The party was already over so everyone was gone anyway. I still got text from my parents and sister asking where I was and where my daughter was and why did we leave. I didn't respond. <br><br>They called me the next day yelling at me for "taking it too far this time" and that I was "punishing them for trying to make my daughter part of the family". I told them that giving my daughter a loan for $6,000 is not "making her part of the family" but they told me that they would've paid her back if I "hadn't blown things out of proportion". I told them that I will pay my daughter back and that they shouldn't worry about her part but to pay back my sister who paid for both the food and the decorations since my parents gave her my daughter's money. They told me that I was being unreasonable and that they're not trying to "take Advantage of my daughter's money" but that they needed the help. I told them that I would've gladly helped but they didn't ask me because they know I'd say no so they went for my daughter's money. They didn't answer that. <br><br>Now they're mad at me for keeping their money and my sister is mad at me for "being too harsh on our aging parents". I told them that from now on they're not allowed around my daughter and my son until they pay back the $6,000 they took from her.