@eleanorkonik In almost all deer species it is only the male, and never the female, that grow antlers.
You are correct that Reindeer are an exception to this rule.
More info here if you want to read up on why Reindeer are the exception: https://www.discoverwildlife.com/animal-facts/mammals/why-do-female-reindeer-grow-antlers/
@eleanorkonik The link also explains why Rudolph specifically was likely female (females retain their antlers later into the season than males)
@freemo girl reindeer have antlers tho right?? I feel like I once heard a passionate explanation that Rudolph was probably female.