When I Broke My Little Sister's New Toy...

So here’s the deal. I’m the middle child in my family of three siblings. My older brother is 17, and my little sister just turned 8. She got this brand new doll for her birthday last week that she was super excited about, and it had a bunch of fancy accessories and everything. My parents let us go to this big outdoor fair at the park on Saturday morning, but my little sis insisted we take her new doll with us even though I warned her it wasn’t a good idea... and guess what? She dropped it while we were running around and one of those glass candy vendors had an accident right nearby. The doll’s arm got all bent up and broken in the middle of the fair... not cool, but honestly it was my sis’s own fault for being so reckless with something new and fragile... So I try to brush off my guilt by thinking that hey, it could’ve happened to anyone, right? But then a few days later she tells me how much her doll meant to her, saying it would be okay if we could fix the arm but that makes me feel worse. Because now she’s not just sad about losing one of her birthday gifts, but also disappointed in me for letting something happen to it at all... I know I should’ve been more responsible and maybe stopped her from bringing it or told her exactly how careful she had to be, but instead I kind of zoned out and let it slide... What do you think? Am I the asshole here?