Jamie is surely one of the most common characters. As her husband, he would play a major role in the fanfic. He could be there for doctor's appointments, helping her with morning sickness, and sharing in the joys and concerns of the pregnancy. Danny could also be a key character. Maybe he gives Eddie some advice based on his own experiences as a father, or he could be involved in a case that somehow ties in with Eddie's pregnancy situation.
Erin might be another character often featured. She could be a source of support for Eddie, like taking her shopping for baby clothes or just being there to listen when Eddie has pregnancy - related worries. Frank could also be in the fanfic. He might have a more paternal role, perhaps giving his blessing to Eddie and Jamie for this new chapter in their lives, or having a conversation with Eddie about how the Reagan family will welcome the new baby.
In addition to the main family members, some fanfics might include Eddie's friends from work. They could be helping her out with her duties when she starts to have difficulties due to the pregnancy. For example, they cover for her during a shift when she's not feeling well. And there could be interactions between them that show the camaraderie within the Blue Bloods world while Eddie is pregnant.
A practical answer is Chapter 11, because it turns the idea into a concrete scene. The chapter opens with After a meeting, Shang Shaojing pinched the bridge of his nose, tired, and..., adds pressure through Qin, could you pour me a cup of tea as well?, and ends on Miss Qin, please accompany us to.
Chapter 44 is the strongest chapter-level answer because it starts from But the next move by the production team proved they hadn't forgotten the... and follows through on Does anyone here know how to drive?.
If you want the clearest chapter reference, go to Chapter 21. Early on, Jiang Li's clear and logical explanation had everyone stunned in place.; later, the chapter leans on Jiang Yan had wanted to defend Su Yinwan since his sister's temper in the....
The best chapter pointer here is Chapter 40, "The National Museum Speaks!". It opens with [Jiang Li claims she copied this herself? and closes on The handsome guys on this show are so difficult to deal with..
If you want the clearest chapter reference, go to Chapter 32. Early on, You should know, an ID photo is like a mirror for demons.; later, the chapter leans on Even celebrities can't handle going barefaced under the attack of a....
If you want the clearest chapter reference, go to Chapter 43. Early on, The moment He Yun willingly sat next to Jiang Li and even took off his...; later, the chapter leans on Movie Emperor He, where's your aloof persona?" "Waaah, He Bao, Mommy....
If you want the clearest chapter reference, go to Chapter 21. Early on, Jiang Li's clear and logical explanation had everyone stunned in place.; later, the chapter leans on Jiang Yan had wanted to defend Su Yinwan since his sister's temper in the....
If you want the clearest chapter reference, go to Chapter 44. Early on, But the next move by the production team proved they hadn't forgotten the...; later, the chapter leans on Since the Southwest Plateau area was economically backward, the airport....
If you want the clearest chapter reference, go to Chapter 12. Early on, Qin?" Jiang Li called out twice, and only then did Mrs.; later, the chapter leans on Qin, who was standing by the dining table, respond..
Chapter 16 is the strongest chapter-level answer because it starts from Just as the words fell, Jiang Shixu swiftly cast his eyes downward. and follows through on Jiang Shixu panicked, set down the bowl, and reached forward to grab her....