Just a reflection: relationships

​Yes. Half-siblings are related by blood, even though they share only about 50% of their immediate family connection through one biological parent. Let me clarify what that means.

🧬 What does it mean to be half-siblings?

Half-siblings share one biological parent—either the same mother or the same father—but have different other biological parents.

For example:

• Same mother, different fathers: You are half-siblings.
• Same father, different mothers: You are half-siblings.
• Same mother and father: You are full siblings.

🧬 How much DNA do half-siblings share?

• Full siblings: Share approximately 50% of their DNA, on average.
• Half-siblings: Share approximately 25% of their DNA, on average.

The important distinction is that the 50% figure for half-siblings refers to the proportion of their parents they share, not the percentage of DNA they share with each other.

❤️ Are half-siblings related to the other half of the family?

Yes! If you share a biological father, for example, you are biologically related to your half-sibling’s mother’s family through your half-sibling’s connection to that family? Not directly by blood, unless you share additional biological ancestors.

Here’s the distinction:

• Your shared biological parent’s family: You are both related by blood.
• Your half-sibling’s other biological parent’s family: You are not normally related by blood to that side of the family unless you have other shared ancestors.
• Your half-sibling themselves: You are biologically related, regardless of whether you share a mother or father.

One important question

When you say, “Are you related to the other half even if 50% by blood?” do you mean whether you are related to your half-sibling’s other family, such as their mother’s relatives if you share the same father? Or do you mean whether your half-sibling is still your biological relative even though you have different mothers or fathers?

Chatgpt