TGB - is there a built in way to make one behavior run before the others?

I'm trying to create a behavior to initialize the variables of an object (ie: %this.speed, %this.acceleration, %this.health, etc). I'd like this behavior to execute once (and only once) before any other behaviors. Is there a built in way to do this using TGB?

I could manually set this up using a "boolean" variable at the end of my "constructor" behavior, and a conditional statement at the beginning of every other behavior, but I'm thinking that there might be a less clunky way... is there?