Because siblings don't share the exact same DNA. Personality is what you are, behaviour is the result of the influences you had + personality.

You and I or twenty people and I can be raised under the same hardships but personality makes the outcome different.
The result will be mostly (in my case) broken souls, anxiety (nervous, low self-esteem), agression, accepting everything without wondering/asking, depression, suicides, addictions or the opposite of all this because of the personality of that person.

No need to feel sorry, you did not take part in it
A great Sunday.

🍀♥️