Infantile Esotropia: This condition is a common cause of crossed eyes in infants, often appearing in the first few months of life. It's characterized by an inward deviation of the eyes and can be associated with other ocular and systemic conditions.

Accommodative Esotropia: Although less common in infants as young as one month, this condition can occur if there's a significant refractive error that causes the eyes to turn inward to focus.
Nasolacrimal Duct Obstruction: While not directly causing crossed eyes, the constant tearing and irritation from a blocked tear duct can lead to a pseudostrabismus appearance or contribute to the development of actual strabismus due to chronic eye rubbing.
Pseudostrabismus: This condition gives the appearance of crossed eyes due to the shape of the face or the presence of a wide nasal bridge, but the eyes are actually aligned properly when examined closely.

Retinoblastoma: Although rare, this serious eye cancer can cause strabismus (crossed eyes) among other symptoms like leukocoria (a white reflex in the pupil). Early detection is crucial for treatment and survival.
Cataracts: Congenital cataracts can cause visual deprivation, leading to strabismus or nystagmus. Prompt diagnosis and treatment are necessary to prevent long-term vision problems.
Glaucoma: Infantile glaucoma can cause enlarged eyes, tearing, and light sensitivity, and if not treated, can lead to vision loss and potentially strabismus.

Duane Syndrome: A rare congenital disorder characterized by limited horizontal eye movement, which can cause esotropia (crossed eyes) or exotropia (outward turning eyes).
Moebius Syndrome: A rare neurological disorder that can cause facial paralysis and impaired eye movements, potentially leading to crossed eyes.
Congenital Cranial Nerve Palsies: Abnormalities in the nerves that control eye movement can result in strabismus. These are rare and often associated with other systemic conditions.