Opening the letter
Opening the letter, I learned that I was not biologically related to my parents—hence the adoption comment from my sibling.

The letter detailed the circumstances of my adoption and the love my parents had for me despite the secrecy.
It also revealed a substantial inheritance left by my biological parents, which my adoptive parents had kept secret to avoid family conflicts.
Unfolding these truths felt liberating, finally understanding why I had been left out initially.