I need to count all children in third level in a Firebase database.
here is my database structure :
Level 1
 - CHILD1
   - - subchild11
   - - subchild12
- CHILD2
   - - subchild21
I need to get the count (in this case it's 3) of elements in third level ( subchild11 , subchild12 , subchild21)
