Tibial Hemimelia: A rare congenital condition characterized by the partial or complete absence of the tibia, often associated with other limb abnormalities such as missing toes and bowed legs. The presence of both missing toes and a bowed leg makes this condition a strong candidate for the single most likely diagnosis.

Fibular Hemimelia: Another congenital condition involving the partial or complete absence of the fibula, which can also lead to limb deformities including bowed legs and toe abnormalities.
Congenital Pseudarthrosis of the Tibia: A condition where there is a false joint in the tibia, often leading to deformity and potential for missing toes due to associated vascular and nerve issues.
Amniotic Band Syndrome: A condition caused by entanglement of limbs in fibrous amniotic bands during fetal development, potentially leading to a variety of limb deformities including missing toes and bowed legs.

Neurofibromatosis Type 1 (NF1): While less directly associated with the specific combination of missing toes and bowed legs, NF1 can cause a wide range of skeletal abnormalities, including tibial dysplasia and pseudarthrosis, making it crucial not to miss due to its systemic implications and potential for malignant transformation.
Osteogenesis Imperfecta: A genetic disorder leading to brittle bones, which could potentially result in deformities and fractures that might mimic or contribute to the appearance of bowed legs, although missing toes are less commonly a direct result.

Kyphomelic Dysplasia: A rare skeletal dysplasia characterized by congenital bowing of the long bones, which could potentially include the tibia, and other skeletal abnormalities.
Campomelic Dysplasia: A rare genetic disorder that affects the development of cartilage and bone, leading to various skeletal abnormalities, including bowed legs, although missing toes are not a hallmark feature.