Plant growing on top of another plant

[PaigeTheFishKeeper]

Basically I’ve just started growing plants in my aquarium. But I’ve stumbled Upon a newly sprouting plant is growing on one of my other plants. I don’t know exactly what to do? It’s stuck/attached onto the leaf. Advice?

 

[Colin_T]

Leave it alone. Some plants produce baby plants that grow from the end of the leaf.

What are the lines on the glass in the first picture?
They look like Hydra.

 

[Carolyn N]

Looks like Java Fern. Baby plants will form on the leaves. Looks like several plants are planted in the sand. The plant should be attached to a piece of wood, rock, or decoration with string, rubber band, or Gel Super Glue. If planted in the sand, the roots will rot.