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Shortly after the beginning of the Cylon occupation of New Caprica, her daughter Kacey Brynn is taken by Leoben Conoy and used very convincingly to psychologically torment Kara Thrace by passing the child off as Thrace's own daughter, allegedly the result of experiments with the pilot's removed ovary ("Occupation," "Precipice").
With the Second Exodus, Brynn is shocked to discover Kacey alive and well, when Thrace returns to Galactica with Kacey in her arms. By pure chance, Brynn is among many civilians brought aboard Galactica and notices Kacey in Thrace's arms. The two are reunited after four months apart. She thanks Thrace and carries on with the other surviving civilians, making their way to their temporary homes on the hangar deck (Exodus, Part II).
Some weeks later, Brynn surprises a very angry and confused Thrace, letting her know that Kacey has been asking about her. Thrace rebuffs them initially, but after being rebuffed by Admiral Adama, Thrace visits Brynn and Kacey on the hangar deck (Torn).