By Sandra Rose  | 

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Will Smith says he considered killing his father to "avenge" his mother for the years of abuse he inflicted on her.

In an excerpt from his memoir titled WILL, the 53-year-old Philly native recalled how his dad Willard Carroll Smith Sr. - who died of cancer in 2016 - was violent towards his mother, Caroline Bright.

Smith, born Willard Carroll Smith Jr., said his father "terrorized" their family with his strict, overbearing standards, and Smith vowed to make him pay one day.

The actor, rapper, and film producer explained how a shocking childhood incident between his parents "defined" who he is today.

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In the excerpt from WILL, he wrote: "My father was violent, but he was also at every game, play, and recital. He was an alcoholic, but he was sober at every premiere of every one of my movies."

"He listened to every record. He visited every studio. The same intense perfectionism that terrorized his family put food on the table every night of my life...

"When I was nine years old, I watched my father punch my mother in the side of the head so hard that she collapsed. I saw her spit blood. That moment in that bedroom, probably more than any other moment in my life, has defined who I am."

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The Men in Black star, pictured with ex-wife, Sheree, and his mom in 1993, admitted he puts on a front to hide his emotional scars.

"Within everything that I have done since then — the awards and accolades, the spotlights and attention, the characters and the laughs — there has been a subtle string of apologies to my mother for my inaction that day," he continued. "For failing her in the moment. For failing to stand up to my father. For being a coward.

"What you have come to understand as 'Will Smith,' the alien-annihilating MC, the bigger-than-life movie star, is largely a construction – a carefully crafted and honed character – designed to protect myself. To hide myself from the world. To hide the coward."

One day, when Smith was caring for his terminally ill father, he worked up the nerve to avenge his mother for all the years of abuse.

For a fleeting moment, Smith considered shoving his father, who was in a wheelchair, down a flight of stairs.

"As a child I'd always told myself that I would one day avenge my mother. That when I was big enough, when I was strong enough, when I was no longer a coward, I would slay him.

"I paused at the top of the stairs. I could shove him down, and easily get away with it. As the decades of pain, anger, and resentment coursed then receded, I shook my head and proceeded to wheel Daddio to the bathroom."