Sudden onset weakness of left le without any pain or painful swelling of joints is due to neurological problem., What is the child status for Polio immunization? Is he recieved full vaccination schedule
Some times scurvy, septic arthritis
will present as pseudo paralysis
.Is there any weakness of left upper limb? So consult your Pediatrician
for the examination of your child and the assessment of weakness and neccessary investigations.