I really can't imagine that you will have a problem. It just doesn't seem plausbile that your association would give you grief. It would mean then that every "married' couple buying there would require each spouse to be over the age of 55 which wasn't the case when you purchased.

It's best not to stress over this until you speak to your association. And, show them proof of your age.
As for children legally inheriting a condo from their parents that, too, is mentioned in the condo docs. And, the condo docs I've seen reference this as stating they have the right to own the unit.

I am not sure this will help - I have attached a link for the Florida Commission on Human Relations which deals with fair housing. 55+ communities are registered and do not have to comply. You can check to see if you community is truly a registered 55+ and check the facts to see if you have any recourse regarding the situation. It is a tricky thing. I hope this helps.