Summary

• Brett's decision to adopt the abandoned baby isn't taken lightly; it's personal to her because she was also given away by her biological mother.
• Brett's fixation on the infant's safety is explained by her own past experience with a premature birth and the death of the mother, which left her obsessed with making sure the baby is safe.
• Casey, who has always wanted to be a father, proposes to Brett despite the sudden addition of a baby to their relationship, showing that her adoption doesn't pose a problem for their future together.

Chicago Fire season 11 solves an eight-year mystery about Sylvie Brett. In season 11, One Chicago's Chief Boden's people at Firehouse 51 have dealt with their respective issues on top of their collective duty to protect the Windy City. For Brett, that means continuing to usher her paramedicine program while also being the PIC of Ambulance 61. In terms of personal life, things are back to normal with her boyfriend, Dylan, despite Matt Casey's unexpected return to Chicago. Just when things were starting to settle down for her, however, she was faced with another big decision.

While Chicago Fire season 11 has come to an end, it wasn't without a brand-new plot line for Brett. After responding to a 911 call, she and Violet Mikami have to deliver a baby prematurely. While they do a great job, they soon learn that the mother's situation is more complicated than just wanting to have her child safely born. Apparently, she doesn't want the baby, eventually giving it up for adoption using Firehouse 51's anonymous door. That is when Brett decided that she wanted to adopt the newborn herself.

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Brett’s Own Adoption Explains Her Fixation On The Orphaned Baby In Chicago Fire S11

Brett Related To The Child Because She Was Also Given Away By Her Biological Mother

Brett's decision to adopt the abandoned child isn't made lightly in Chicago Fire season 11. She has ruminated about it for a while, even dropping by Chicago Med to check up on the child. As someone who works in their industry, Firehouse 51 members are told not to get personally attached to the people they help because it could be emotionally draining. For Brett, however, adopting the baby is personal. Brett explained to Chief Boden that she sees herself in the child because she was also given away by her biological mother who couldn't take care of her.

This is new information about Brett — something that she hadn't really discussed in the past. The fact that the infant's mom is the same age as hers when she was put up for adoption motivates her further to take care of the newborn. Aside from its implication on her future, this resolves an eight-year mystery from season 4. In one of her first calls with Chili, Brett worked hard to deliver another baby prematurely. The mother, unfortunately, died, which made Brett obsessed with ensuring the newborn's safety. Nobody understood why she was so fixated on the infant until now.

What Brett’s Baby Adoption Means For Her Relationship With Casey

Casey Was Always Meant To Be A Father

Casey returns to Chicago in time for the final episode of Chicago Fire season 11. Casey and Brett have had a will-they-won't-they relationship for a while now, and while a baby suddenly coming into the picture could easily have been a burden, that doesn't stop Casey from proposing. Ultimately, Brett adopting the baby shouldn't be a problem for him. It has always been clear that Casey is meant to be a father. The fact that he moved across the country to take care of his late friend's kids proves that.