The sign for "relation" can also mean "cooperation."

To show a relationship between two people, things, or ideas you can use a back-and-forth sliding movement between the two items. This sign can also be used to mean "cooperate."

RELATION / COOPERATION:

You can also use the general sign "CONNECT" to indicate that two things are related or connected to each other. That they have a "bond."

CONNECT:

Also see "CONNECT"

Also see: "OF"