Help with functions

Phaser 3
1

I have a function that holds the properties of my enemy tank. However, I want the turret to stay on the tank which requires it to be in update but it doesn’t seem to stick to the tank. Is there a way to call update within the function. Here is my code:

enemyPlayer = function (game, player, x, y, bullets) {

//console.log(index);
var x = Phaser.Math.RND.between(0, 800);
var y = Phaser.Math.RND.between(0, 600);

  this.game = game;
  //this.tank.name = index.toString();
  
  
  this.health = 3;
  this.player = player;
  this.bullets = bullets;
  this.fireRate = 1000;
  this.nextFire = 0;
  this.alive = true;

  this.tank = this.physics.add.sprite(x, y, 'enemy', 'tank1').setOrigin(0.5, 0.5);
  this.turret = this.physics.add.sprite(x, y, 'enemy', 'turret').setOrigin(0.3, 0.5);
  /*this.turret.x = this.tank.x;
  this.turret.y = this.tank.y;*/

  
  this.tank.body.immovable = false;
  this.turret.body.immovable = false;
  this.tank.body.collideWorldBounds = true;
  this.turret.body.collideWorldBounds = true;
  this.tank.body.bounce.setTo(1, 1);
  

  this.physics.velocityFromRotation(this.tank.rotation, 100, this.tank.body.velocity);
  this.physics.velocityFromRotation(this.tank.rotation, 100, this.turret.body.velocity);

};

The 2 lines I have commented above are required to be in update otherwise the turret just sticks with the boundaries.