QUESTION: How realistic is it for a man in his early twenties to have few conscious memories of his childhood? What could account for this volume of lost information (if it's even possible)?
Additional Information: The protagonist was put up for adoption at age two, because his mother had died and his father was unable to support him. After only a few months, he was adopted and raised by an older couple. He has convinced himself that his childhood somehow doesn't "count" because of his father's absence. He is also convinced that he can restore a traditional father/son relationship, and is obsessively looking for him. It seems he holds little or no value in his life with his foster parents, so I can see how he could ignore those years to the point of outright forgetting them.
ANSWER: It's plenty realistic, if it's happening for the reason it normally happens.
What you're talking about is referred to as "repressed memories," or memories that have been pushed down/away from the conscious because they're too painful to recall. Repression, in other words, is a defense mechanism. Painful can mean a lot of things. Humiliating, scary, incredibly sad, confusing, etc.
Not knowing much about your story, I would suggest that perhaps you put the protagonist up for adoption just a bit later in life. I think you need to give him a bit more time to attach to his dad and theoretically have made some memories to repress. I mean, let's face it, most people's first memories are from age three or four or even five years old in the first place. This is arguably because a) The brain hasn't developed far enough to retain memories in an adult way or b) The child hasn't yet developed enough language to store the memories in a way that can later be retrieved by the adult brain.
If your protagonist is put up for adoption at age five or six and then has few memories of his childhood, perhaps including after he got adopted, you've got something pretty darn realistic as far as repressed memories go. It would also help if the couple who adopts your protagonist is not an ideal family. They can be good people, but perhaps they don't really know how to relate to a child and so they're distant, or aloof, or just extremely busy with their own lives. Or maybe they're not great people--not abusive, per se, but maybe they're cold and critical, and your protagonist unconsciously puts his father on a pedestal and that's why he's obsessive about finding him as an adult. I could see someone discounting his life with his adoptive parents if they were never really "there" for him emotionally, and yearning for a connection with this father he's built up in his head.
I hope that's helpful! Let me know if you have additional questions!
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