we just got done pulling our 3rd backwards calf. the first 2 were out of 2nd calf girls..this one was out of a heifer. we only had 8 calves. 3 backwards? i need to know what could cause this..people say just bad luck, but i find it odd that we had 3 in 1 year. we saved the first 2..this one didnt make it. any thoughts?