Factor XIII (FXIII) deficiency is a rare bleeding disorder, which can result in life threatening hemorrhage. Rarer still is acquired FXIII deficiency, in which the disorder is due to autoantibodies that inhibit the factor. To describe one of the youngest reported patients with this condition. To discuss the challenges we encountered in monitoring response with the available assays. To review the literature and provide a review of all acquired FXIII cases. We present the case of our patient, a 9-year-old girl with acquired FXIII deficiency. We present a comprehensive review of all acquired FXIII deficiency cases reported globally in English, with focus on clinical presentation, diagnostic assays, treatment and prognosis. There is no current standard for therapy and measuring response to therapy can be complicated by limitations of assays in the presence of inhibitors. Clinicians should be aware of acquired FXIII deficiency as a potentially life threatening bleeding disorder even in young children. The case presented illustrates a young patient with acquired FXIII deficiency with a good clinical response to cryoprecipitate and difficulty in hemostasis monitoring utilizing clinically available assays.