Selfish, but can’t help it

I just found out my boyfriends sister is also pregnant. It is so selfish of me, but I am really upset about it. This is my boyfriend and I’s first kid (she’s already had one) and now our spotlight has been taken, and our sons as well. His parents treat his sister so much differently than him and that doesn’t help our case at all...

I know this is selfish, but I needed somewhere to vent & know you guys won’t judge me.