Yes a 3 year old or any child of any age can have appendicitis.
The condition appendicitis usually happens in older children and adults most commonly.
However 2 year olds and 3 year olds can also have appendicitis as well.
Children between 2 and 5 years old who have appendicitis may experience stomachaches and vomiting as well as loss of appetite and fever.
An appendix that bursts can kill the person or toddler with appendicitis so if you think your 3 year old is having appendicitis then you should take the 3 year old to the emergency room because they may need the appendix removed through surgery.
So get the 3 year old to the emergency room or urgent care as soon as possible if you think your toddler or 3 year old child is having appendicitis because it is possible for a 2 year old and 3 year old to have appendicitis.