Accidental trauma: This is the most likely diagnosis given the age of the child and the context of a fall. Children at this age are prone to falls due to their curiosity and lack of coordination, and most falls result in minor injuries.

Fracture: Given the mechanism of injury (a fall), a fracture is a plausible diagnosis. Children's bones are softer and more prone to greenstick fractures or other types of fractures.
Head injury: Falls can often result in head injuries, ranging from minor bumps to more serious conditions like concussions or skull fractures.
Soft tissue injury: Bruises, scrapes, or other soft tissue injuries are common after falls.

Abusive head trauma (Shaken Baby Syndrome): Although less likely, it's crucial to consider non-accidental trauma, especially if the history provided does not match the severity of the injuries or if there are inconsistencies in the story.
Spinal cord injury: Though rare, spinal injuries can occur from falls and are critical to identify early to prevent further damage.
Internal injuries: Internal bleeding or organ damage can occur from severe falls, especially if the child fell from a significant height or landed on a hard surface.

Pathological fracture: If the child has an underlying bone condition (like osteogenesis imperfecta), a fall could result in a fracture more easily than in a healthy child.
Infection: If the skin is broken from the fall, there's a small risk of infection, especially if the wound is not properly cleaned and cared for.
Childhood cancer: Though extremely rare, certain types of cancers (like osteosarcoma) could weaken bones and make them more susceptible to fractures from minor falls. However, this would be an unusual presentation for cancer.