Hi! I'm a newbie in HTML5 and panda.js. How will I remove a sprite on collide. I am studying your sample game Flying dog, and I would like to place an image on your goalBody with a Sprite. (Just like what you did on topSprite and bottomSprite). But I am having an error if I add this code on collide. this.goalSprite = new game.Sprite(game.system.width + this.width / 2 + this.width + game.scene.player.body.shape.width, topHeight + this.height / 2, 'media/someimage.png', { anchor: {x: 0.5, y: 0.5}, });game.scene.goalContainer.addChild(this.goalSprite);this.goalBody.collide = function() { game.scene.world.removeBody(this); game.scene.goalContainer.removeChild(this.goalSprite); //this is the line I added game.scene.addScore(); return false; };Error:Uncaught Error: undefined The supplied DisplayObject must be a child of the caller [object Object] Am I doing it right? Or is there better approach on this? BTW, Panda.js is really amazing... Thanks,