Turn on and off ParticleSystem and LineRenderer on same object at the same time

I have an object that has a LineRenderer and a ParticleSystem on it and its a child of another object. I am trying to turn the renderer off for both so they are not visible till they are turned on. Here is what I’m using:
private Renderer objectParticles;
void Start () {
objectParticles = gameObject.transform.Find(“spawnCast”).GetComponent();
objectParticles.enable = false;
}

The problem with this is it seems to only turns off the LineRenderer on the child object and not the ParticleSystem Renderer too.

Without seeing how the gameObject is set up in Unity it is hard to know what you are actually doing there since you are finding a child by name and then using GetComponent without a type specified. This is probably a better solution:

private Transform childObject;
private ParticleSystem objectParticles;
private LineRenderer objectLineRenderer;

void Start()
{
childObject = gameObject.transform.Find("spawnCast");
objectParticles = childObject.GetComponent<ParticleSystem>();
objectLineRenderer = childObject.GetComponent<LineRenderer>();

objectParticles.enable = false; 
objectLineRenderer.enable = false; 
}

Without seeing what ‘Spawn Cast’ is I don’t know how you have set it up but that should work. You might want to assign the child object via a different method though as find is pretty slow. Also you could use objectParticles.Play(); and .Stop(); instead of enabling and disabling it which may work better for you in the long run.