In my game I am tracking all player ships as well as all selected ships, which will be a subset of all player ships. I add the ship to the allShips list, then add it to the selectedShip list when selected. After adding it to the second group it seems to be removed from the first group. Is this intended behavior? Example: function create() { game.physics.startSystem(Phaser.Physics.ARCADE); game.world.setBounds(0, 0, 800, 600); this.game.stage.backgroundColor = '#71c5cf'; firstgroup = game.add.group(); secondgroup = game.add.group(); // Add the test fighter testFighter = game.add.sprite(400,200, 'yellowship'); firstgroup.add(testFighter); console.log('FIRST GROUP LENGTH BEFORE ADDING TO SECOND GROUP: ' + firstgroup.length); secondgroup.add(testFighter); console.log('FIRST GROUP LENGTH AFTER ADDING TO SECOND GROUP: ' + firstgroup.length);}Console output: "FIRST GROUP LENGTH BEFORE ADDING TO SECOND GROUP: 1""FIRST GROUP LENGTH AFTER ADDING TO SECOND GROUP: 0" Thanks!