Hi greeting, My 3 and half year old child eaten 35...

Folic acid overdose
Folic acid is considered one of the essetial vitamins in the body that are supplied by the food to get invloved in process of cell structure and red blood cells production. Folic acid is not considered a toxic supplement, herald no side effects and carry no side effects when overdosed. Attention should be paid toward the possibilty that the child might ingested other medications alongside the folic acid . if not no need for further follow up .
Required investigations 
There is no need to perform any invetigation if the child intake was only of folic acid. but if suspicious, you should do cbc to detect blood hemolysis, Kidney functions to reveal elevated kidney functions and liver function tests to detect any signs of liver failure 
Alarming signs 

• Repeated vomiting 
• Rectal and nose bleeding 
• Jaundice 
• skin bruises 

Our advice
You are adviced to maintain good hydration of the child in addition to a healthy diet, and keep any medication away from the child reach