I know we are in a civilized world but we have to understand what is normal, meant to be and what is not normal. These days, we now see people who gwt married to their siblings and even cousins. Why would we do that?
It is highly prohibited by God to marry your kin or a close relative.
In the Bible, Leviticus 18:6 says, None of you shall approach to any that is near or kin to him, to uncover their nakedness: I am the Lord.
It’s very necessary to hear the word of God. Having sexual relations with your family member is bad. This isn’t just what the Bible has said but it has been proved scientifically as well.
It’s not even normal to date your family or the first three families or generations close to you.