Beyond mad

My brothers both just had babies with their girlfriends and my mom was super excited for both and now im trying for one and my mom doesnt know. Im super excited for one and my brother announced yesterday that theyre having their third and said it was an oops. Shes supposed to be on birth control and we think she lied just to have another one of his kids because he makes good money. Am i insane for being mad that they took my turn? Is it wrong to think she is trying to ruin his life?