you have a keiki! (a 'pup' or baby plant)
You can remove it and pot it up, looks like there's plenty of root growth - the general rule is to have at least 3" total roots - three 1" roots, or one 3" root, or how ever many roots to total 3" - before removing the keiki. You can also leave it on the "mother" plant as well, if you can keep it happy that way - and right now it looks happy
(to remove keiki, you can gently twist it off the spike)