I believe that even if the Bible does not tell us some things, there are so many things we just have to think about and realize that it is awkward and we should never engage in them.
One of those things is getting married to a close relative. It’s really a bad idea for you to get attracted to your relative or vice versa be it extended or nuclear. Let’s take some Bible passages.
The Bible says in Leviticus 18:6 to us that; “None of you shall approach to any that is near of kin to him, to uncover their nakedness: I am the LORD.”
https://youtu.be/R_GVqSdYWUU?si=gA-V4S1ko5vltmqZ
For He is the Lord and that is why you have to always listen to Him and respect Him by doing all the things that He says.
What did science say? Science itself proves that when cousins or relatives marry each other, they tend to have a child with defects. I mean, birth defects of any kind and this is why in every way, we have to stop or prevent family members from getting married to each other.
If you see that this man or woman is your blood, do not sexually go close to such person. It is dangerous. Tge devil is very cunny and all that he aims at is making sure that the things which are never approved of God happens.
Prevention is better than cure. If you prevent having any sexual relationship with your family, the worse wouldn’t happen. What does the Lord say? Do not open the nakedness of your family member and that’s what you should do.