According to the police report, the boy ordered a smoothie at an Olive Garden in Indianapolis on Thursday night but was mistakenly given a rum drink.
Police say he drank about half of the 4-ounce drink before a supervisor notified the parents about the mistake.
The parents said they took their son to a hospital as a precaution. The boy was alert but a little shaken up.
An Olive Garden spokeswoman says the waitress has been fired. Indiana Child Protective Services is investigating to determine whether any charges should be filed.