A 21-year-old female with a medical history of shaken baby syndrome, leading to intellectual disability and functional quadriplegia, presented to the ED with non-bloody vomiting for one week. She was diagnosed with septic shock, and initial blood counts revealed severe anemia (hemoglobin 2.6 g/dL), thrombocytopenia (platelet count 50k/uL), and leukocytosis (WBC count 23.3k/uL). The patient received transfusions of 5 units of RBCs and 1 unit of platelets. Hematology was consulted and review of the peripheral blood smear revealed anisopoikilocytosis, scattered macrocytes, few hypersegmented neutrophils, and numerous erythroid precursors. Notably, the erythroid precursors exhibited a left shift with a significant number of proerythroblasts, basophilic, polychromatic, and orthochromatic erythroblasts. Dysplastic changes, including binucleated forms, nuclear-cytoplasmic asynchrony, rare nuclear budding, and irregular nuclear contours, were observed. Mitotic figures and Howell-Jolly bodies were also noted. Additional lab tests revealed low serum vitamin B12 (<175 pg/mL), elevated homocysteine (33 umol/L), elevated methylmalonic acid (403 nmol/L), and normal folic acid (3.6 ng/mL), consistent with severe vitamin B12 deficiency. Flow cytometry confirmed increased erythroid precursors, and next-generation sequencing (myeloid panel) showed no pathologic variants. Although nucleated RBCs can be seen in vitamin B12 deficiency, the unusual presence of numerous erythroid precursors, especially early forms, raised concerns about a possible hematologic neoplasm, suggesting the need for a bone marrow biopsy. The patient was started on B12 injections (1000 mcg daily for 7 days), resulting in a significant decrease in erythroid precursors, improvement in anemia, and normalization of WBC and platelet counts. Given the negative molecular studies, the likelihood of hematologic malignancy is reduced, and a bone marrow biopsy is not necessary at this time. The patient has been advised to continue oral vitamin B12 and will follow up for further evaluation.