Ok
same mom different dad= half sibling
same dad different mom- half sibling
different mom different dad- step sibling
same mom same dad- full blood..
Now that we got that settled... Sorry I read someone say that they r related by blood.. They arent they r related by marriage... I have 3 step siblings one full blood brother and one half sibling so I know the difference... I dont think there is anything wrong or anything to be ashamed of with your partners family being tied into yours by marriage..