Well, a lot of sibling rivalry fics in the fandom fall into obvious tropes—the jealous older brother who bullies Harry, or the resentful one who feels ignored. 'The Forgotten Older Brother' takes a different path that honestly feels more psychologically real to me. The rivalry isn't a constant shouting match; it's a quiet erosion of identity, where the older brother's entire existence is defined in relation to 'the boy who lived.' His magical abilities might be average, his achievements overlooked at Hogwarts, and his parents' worry is always laser-focused on Harry's survival, not his own future.
What I found compelling was how the fic uses magical lore to mirror the emotional dynamic. The brother might stumble upon obscure, foundational magic—ancient runes or creature husbandry—fields considered unglamorous compared to flashy Defense Against the Dark Arts. His mastery there becomes a form of silent rebellion, building a world where he is the authority, not Harry. The rivalry becomes less about direct conflict and more about two siblings operating in completely different spheres of the same magical world, one in the blinding spotlight and the other in the shadowy, deep archives, each nursing a different kind of loneliness.
It doesn't fully villainize either side, which is its strength. Harry is often portrayed as confused and guilty, aware of the disparity but too burdened by his own fate to properly address it. The real antagonist is the external pressure of prophecy and war, which forces their relationship into a distorted shape. The resolution, if the story has one, usually hinges on the older brother's niche knowledge unexpectedly becoming crucial to the war effort, forcing a re-evaluation of what 'power' and 'value' really mean within their family. It’s a slower, more melancholic burn than most fics with this premise.