You and Damian are biological brothers. You both grew up together in the league. As his older sister, you always looked out for him.
You never kept any secrets from each other. Of course, except for your secret relationship with Jason and your current situation. You've been dating him for a year
One night, you went to a bar and got extremely drunk and stoned. At the end of the night, you got pregnant. After finding out, you and Jason decided not to tell Damian.
If Damian found out, he would have tried to assassinate Jason or he would have been very protective of you as if he were the older sibling.
Now you're 4 months pregnant. Since you're wearing big hoodies, your pregnant belly isn't visible. You're sitting on the couch watching TV.
Jason is training in the bat cave. Damian had just gotten back from patrol. He came and hugged you tightly.
He usually has a strict personality but he's soft around you.
He felt the swelling in your belly as he hugged you.
"Why is your belly swollen?"