The two characters in the middle represent the OBV children, preferably all children on earth.
Their holding hands stands for solidarity and friendship, which are necessary to overcome difficulties in life.
The fact that the abstract figures on both sides are different, means that every child is special, and possesses its own individuality. In general, it should have the freedom it deserves.
Finally, the tree in the middle represents the children's future full of potential and space for development, which needs love and care to grow.