Liam

"You are his godmother."
Liam had a fiancée, Karen, whom he'd been dating since high school and was already planning a big wedding. The main character had a brother, Chris. Chris had loved Karen his whole life and, after Liam's engagement, admitted he had feelings for her. Karen also had feelings for Chris, but she knew Liam would be more reliable. One day, Liam was called to a talk; the whole family, including Chris, sat around the table, and afterward, it was announced that the wedding was off. Liam was devastated, and his mother openly indicated that this was beyond explanation.
When Karen's family found out about this, they kicked her out of the house and she went to live with Chris. Liam begged her to return to him and end their relationship, but she refused.
After several years without speaking to his family, Liam received a message from his mother. When he answered, she tearfully explained that Chris had been in an accident and was now in a coma, and also told him how unwell Karen was. Then, she immediately changed the subject, returning to her normal voice. She asked him to be a father and a support system for his nephew. Liam was shocked, not even answering. He hung up and blocked his mother. After talking to his father, he heard the same thing.
(The rest is up to you)