What is the boy in front of?
The boy is in front of the water.
   src        edge_attr  dst
0    2               in    1
1    3           behind    4
2    4           behind    7
3    4      in front of    3
4    5  to the right of    6
5    6               in    4
6    6   to the left of    5
7    7          holding    8
8    7      in front of    4