The story starts from the perspective of the mother — a beautiful woman, overwhelmed by hard work. For this role I am looking for an actress with an old-fashioned nostalgic look, like she has just stepped down from old photos. She should be around 40, but so she could easily look younger with make-up applied. It is a petite and frail woman, and viewers would feel pity seeing her carrying her son on her back, him tumbling her down and hitting with his long limp legs.
The child is barely shown in the beginning, he appears fleetingly and characterless, and his name is mentioned in the script only after a while. He is portrayed by different kids. The first one should be a year or a year and a half. It is a strong and energetic kid, who started walking and even running quite early. The second is 2-3 years old. It is a boy with a developing muscular weakness. For the role of 11-years old character I am willing to find an actor with a spinal atrophy or a similar diagnosis. Patients with spinal atrophy usually are very intellectually advanced. They have exalted faces and intelligent looks, but disproportionate bodies: pronounced spine deformation makes upper body appear smaller, one leg is usually set on top of another to keep balance.