In The Summer I Turned Pretty TV series, Susannah’s letter to Conrad is a heartfelt wedding-day note where she reflects on seeing him truly in love and what she wishes for his future.

What the letter essentially says

Susannah tells Conrad that:

  • She has only ever seen him in love once , and for that she will always be deeply grateful.
  • It wasn’t just seeing him in love that moved her, but seeing how the girl looked at him, like he was the only boy in the world.
  • As a mother, nothing made her happier than watching her son be so loved and cherished by someone else.
  • She hopes that the person he marries will love him even a fraction as much as the girl she saw him with did, because that love was so strong and rare.
  • She never outright says he is marrying Belly, just that the love she witnessed (clearly implying Belly) is the standard she wishes for his future.

In short, the letter is Susannah saying: I saw you in real, deep love once, and it was beautiful; I hope your marriage holds even a piece of that same kind of love.

Why fans are talking about it now

  • The letter appears in the context of Conrad’s wedding, which instantly raises questions about whether he’s marrying Belly or someone else.
  • Viewers and forum users point out that Susannah is not literally confirming Belly as the bride; instead, she is anchoring her hopes for his future to the one great love she saw him have.
  • This ambiguity fuels ongoing forum and social media debates in 2025–2026 about what the letter “really” means for Conrad and Belly’s endgame.

Quick forum-style recap

The letter tells Conrad that his mom saw him truly in love once, loved seeing him both love and be loved, and hopes his future wife loves him even a fraction as much as that girl did.

TL;DR:
The letter to Conrad is Susannah’s emotional message saying she saw him in one true, deep love, it made her profoundly happy, and she hopes his marriage carries at least a fraction of that same love—without explicitly stating he is marrying Belly.

Information gathered from public forums or data available on the internet and portrayed here.