About a week before her death, Carly gave two letters to Alex: one for him and one for the woman he would one day fall in love with. Alex introduces these letters by reading the one Carly wrote to him. Carly used the last of her strength to convey her desire for Alex to be happy after her death, which she believes he can only achieve by remarrying. This act defines Carly as a woman who was selfless and who loved her family so much that she was able to accept the reality that Alex would want to marry again after her in. To Alex, the letter represents a link to the woman he loved and lost, and a link to the future. If Carly hadn’t been so accepting of the idea of him moving on, he might have been too burdened with guilt to remarry.

Alex fears that if he gives Katie the second letter too soon, she might not be ready for what it has to say. However, when he does give it to her, it comes at the perfect time. Katie finds herself questioning her sanity when she realizes that Jo never lived in the cottage next door and was likely a figment of her imagination.