How many native Esperanto speakers are there?
There are something like a thousand people who have Esperanto as one of their mother tongues. Often this is because their parents come from different countries and met at an Esperanto event. The parents use Esperanto together at home, and when they then have a child, they want to go on speaking Esperanto together. Perhaps the most common situation is where one parent always speaks Esperanto to the child, while the other parent (the immigrant) uses their native language with them. In society, the child uses the local or national language. The child becomes natively trilingual.