Even though he may not be your biological son, you are still his father. I wrote this sentence as it can be a painful thing to say to someone. You would want to ease this kinds of news on to someone by softening the blow a bit.
We use the word "biological" to describe people who are related by kinship or "by blood."
e.g. I was adopted, and I've never met my biological father.
e.g. I just found out that he is not my biological dad because we aren't related by blood.
"biological"という単語を使って、血族関係、血がつながっているということを表現します。
例文
I was adopted, and I've never met my biological father.
（私は養子で、実の父に会ったことはありません。）
I just found out that he is not my biological dad because we aren't related by blood.
（彼と私の血はつながっていないので、彼が私の実の父ではないということが先ほど発覚しました。）
A more informal way of say this is by using the words 'real son' instead of biological. This informal phrase would likely be heard among friends in a casual conversation.
He realized that the boy wasn't his biological child.
"The boy wasn't his biological child." This means that the child is not his real son.
"He realized that the boy wasn't his biological child." This means that he found out that the boy was not his biological son.
例文
"The boy wasn't his biological child."
その子は血の繋がった子供ではなかった
その子供が本当の子供ではないと説明しています。
例文
"He realized that the boy wasn't his biological child."
彼はその子が血の繋がった子供ではないことに気付いた
彼がその子が血の繋がった子供ではないことが分かったということです。
The boy that he raised is not not his biological child.
The son who the man raised is not actually his son by blood.
▪ The boy that he raised is not his biological child.
"raise" is to bring up a son on daughter.
"biological" is when you are related by blood.
This sentence is saying that the son he had raised is not related to him by blood.
▪ The son who the man raised is not actually his son by blood.
"actually" means the facts of a situation.
"by blood" means biologically related.
This sentence is indicating that the boy that the man raised is not really his biological son.
▪ The boy that he raised is not his biological child.
(彼が育てた男の子は彼の実の子供ではありません)
"Raise"は息子または娘を育てることです。
"Biological"は血が繋がっていることです。
この文は彼が育てた息子は彼と血が繋がっていないと言っています。
▪ The son who the man raised is not actually his son by blood.
(その男性が育てた息子は実際は血が繋がった息子ではありません)
"Actually"はある状況の事実という意味です。
"By blood"は血が繋がっているという意味です。
この文は男性が育てたその息子は彼の実の子ではないことを示しています。
There was no biological connection between father and child
The child was not a blood relation
Blood relation - a person who is related to another by birth rather than by marriage.
"Mary is not actually a blood relative as she is Henry's adopted daughter."
Genes - a genes is the basic unit of heredity. Every person has two copies of each gene, one inherited from each parent.
"John is a brilliant mathematician just like his father. It must be something in the family genes that gives both of them that ability!"
Blood relation - 婚姻関係ではなく、出生上の関係があること。
"Mary is not actually a blood relative as she is Henry's adopted daughter."
メアリーは、ヘンリーの養子の娘なので実際のところ血縁関係はない。
Genes -遺伝子とは、遺伝情報の基本的な単位です。人間はそれぞれ片親から1つずつ2コピーの遺伝子を持っています。
"John is a brilliant mathematician just like his father. It must be something in the family genes that gives both of them that ability!"
ジョンは父親のような天才数学者です。そのような能力を2人とも持ち合わせたのは家族の遺伝子によるはずだ。
Although I raised him as my own, he is not actually my biological son.
The boy was not his by blood.
Adopted - the name for a person who is raised by one or two parents that are not their biological parents.
"raised him as my own" - means he was raised in the same way he would have raised his own biological son.
"not his by blood" means not by a biological connection, they do not share the same genes. Family can be referred to as "my blood relatives"
Adopted（養子になった）
- 血のつながりのない親に育てられた人の呼び名です。
"raised him as my own"
-「実の子を育てるのと同じようにして育てた」という意味です。
"not his by blood" は「血のつながりがない」という意味です。「家族」は "my blood relatives"（血縁）と呼ばれることがあります。
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