Boyfriend Loving Sister Over Me. Okay Or No?

So my boyfriends sister just dislocated her arm and he is distraught and very on edge about it. He even started getting emotional because he didn't like seeing her hurt. Which I completely understand. The annoyance is, in a lot of things, he puts her over me. This scenario is an example of that case. She dislocated her arm and she is doing well thankfully, she is at the hospital in the bed and she's not in pain or anything. I messaged him to see how she is doing, as well as himself, and he kept telling me he had to go because he wanted to be vigilant with her (even though in the photos he sent me of her, his mom was on her phone which meant she wasn't in danger or anything) and when I would ask questions about her and her state (which I asked once only), he would get annoyed and tell me not to worry... but like, I was just checking up?
I fractured my back very severely as well as my ankle a couple months ago after I fell off my horse and he was NOT this alarmed. And I notified him before anyone. I was crying because of how much pain and shock I was in. He was just asking if I was alright, he never offered to come pick me up from the barn or take me to the hospital. Let alone get emotional about the physical pain I was in.
I love his sister and I honestly think their bond is really sweet. But it just bothers me a little knowing that he doesn't care for me as much as he does for her.
I just feel like a back injury should have been taken to with more care, especially from him...
Can anyone offer their opinions? I would love to hear them.
Boyfriend Loving Sister Over Me. Okay Or No?
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