Signs Your Father Is Not Biological Father

How confident are you that the man you’ve called dad for as long as you can remember is really your biological dad? You may be wondering if your dad is genuinely your father because you look and act nothing like him. Keep reading if you are currently on the hunt to find out if your father is your biological father. 

Vast differences in physical features and personality traits, as well as inconsistent timelines and a lack of love and affection, are all signs that your father might not be your biological father. However, you will need to undergo a DNA paternity test for definite proof.

Maternity is a matter of fact, but paternity is a matter of opinion. Questions of true paternity are built over the deepest well of insecurity for children searching to know who they truly are. Use the signs listed below to get rid of or to prove your gut feeling. Then, let’s start searching for the truth.

Three generations of men looking in the mirror shaving

Physical Features

Are you concerned that you look nothing like your father? You may even have heard that you look like your mother’s ex. Looking like someone else may cause a lot of suspicions.

Your physical features are direct results of the DNA that you have inherited from your mother and father. Therefore, physical features are usually our first clue to recognize paternal misidentification. 

Eye color inheritance:

It is essential to understand that your eye color inheritance comes from a science called the polygenic inheritance pattern. Simply put, your eye color is determined by more than one gene. 

There are recessive and dominant genes that all play a role in determining your eye color. However, scientists state that recessive genes cannot create a dominant gene (eye color) but, dominant genes can create recessive genes (eye color).

When trying to determine paternity using eye color, this method may be a helpful tool in some respects.

For example, if a supposed father and mother have blue eyes and their baby is born with dark brown eyes. The odds are high that the child may not be the supposed father’s child.

Or if the supposed father and mother both have brown eyes and the baby is born with green eyes. This would not mean the supposed father is not the biological father (dominant genes can create another dominant gene or a recessive gene).

However, it is crucial to note that physical features are not a sure-fire test! For example, many individuals resemble their mother instead of their father. In addition, you may have inherited a pair of recessive genes that neither your father nor mother outwardly manifest.

Blood Types

Blood typing is another possible way to determine paternity. Blood types have similar principles to eye color. 

The dominant blood types are A, B, and AB, whereas the recessive blood type is O.

Now, dominant blood types can create themselves, but they cannot make another dominant blood type.

For example, if the supposed father and mother are both A blood types, they will be unable to produce a B dominant blood type. However, if both parents have A blood types, they can create an O blood type baby (recessive genes).

Regardless, O blood types are recessive genes and can only create themselves. 

So, the supposed father can only be excluded from being the biological father if the baby has a different dominant blood type from his own.

For example, if your supposed father has an A blood type (dominant) and your mother has an O blood type (recessive), and you are born with a B blood type (dominant), there is no possible way for him to be your biological father.

Personality Traits

Your personality traits are also, to some extent, a direct result of DNA inherited by your parents.

Nevertheless, do not be bluffed by statements like inheriting your grandparents’ personality traits or genes that you never knew. If you have no resemblance to your father, it could be a red flag.

Inconsistent Timelines

Inconsistent timelines may be able to confirm your fears about your father possibly not being your biological dad. 

Cross-checking the time of physical presence and the conception period is the most common example of inconsistent timelines. 

Often, we find contradicting stories from parents and relatives that lead to blurry timelines. The claims and rumors might not all be true, but they definitely plant a seed of doubt into your mind.

For example, if you find out that your father was in the military or out of the country traveling approximately nine months before you were born, you are allowed to have strong doubts.

Born out of Wedlock

A child born of wedlock is when a child is born to a woman who wasn’t married from the time of conception to the date of the child’s birth. 

Being born out of wedlock is another factor falling under inconsistent timelines.

It would be best to discuss these inconsistent timelines with your father, mother, guardian, or closest relative.

A Lack of Love and Attention

Parents and siblings often feel an instant sense of deep connection with one another. However, suppose you find yourself perplexed to why your dad showers your siblings with love and affection while being indifferent towards you. In that case, it may be a possible sign that your supposed father is biased towards your siblings because you aren’t his biological child.

Moreover, your supposed father might not even know that he isn’t your biological father, but they have a sixth sense allowing them to feel close to their children. As a result, he might unknowingly love his biological children more than you.

However, indifference towards you is not always a sign of misattributed paternity; it could be something else.

DNA Paternity Test

Even though the signs mentioned above might be justifiable reasons to question if your father is really your biological father, remember that they are not definitive proof. For absolute proof, you will need to undergo a DNA paternity test.

The direct and accurate way to accurately know if your father is or isn’t your biological father is through a DNA paternity test. Your genetic markers are your supposed father’s genetic markers will be compared to find paternal matches.

If you can get your supposed father’s permission to do a DNA test, it will be easy to confirm whether he is your biological father or not.

DNA testing is done by obtaining saliva, cheek swab, hair, blood, or other genetic material. The genetic material undergoes laboratory analysis, and then the material is compared to a paternal index to confirm whether there are paternal matches or not.

Ancestry DNA Test

If circumstances prevent you from acquiring a genetic sample directly from your supposed father, there are other ways to do so.

Basically, you test your own DNA by using a home DNA test for Ancestry kit. Your results will be cross-referenced to a family tree. This way, you can trace distant family members and distinguish whether your supposed father has blood ties to you or not.

The biggest downfall of ancestry DNA testing is that the database must include samples from your family to get the results you’re looking for. 


After many sleepless nights wondering if your dad is your birth father, there is something utterly devastating yet self-fulfilling in knowing if your father is your biological father. I mean, it’s 50 percent of your genetic makeup!

Though many of the above signs might be justifiable reasons to question if your father is your paternal father, remember that they are not definitive proof. You will need to undergo a DNA paternity test to compare your genes to determine if your dad is your paternal father.

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