Unless you count riding past it on the ADO Bus, I have never been to Puerto Morelos.
And I haven't been to an AI since 2003.
But one thing that my wife & I noticed on the El Cid Marina website is that the Kids Club is open until 9 PM. And the pool has waterslides. And Puerto Morelos is the home of Crococun Zoo.
So I have to think that there will be a lot of children there.