Adjusting/Adding Sprites During Dialogue

I am currently working on a project where the user interacts with a character in a 2D UI. I have a script that extracts lines from a text file and displays the text within a text box whenever the player presses the Enter/Return key or the left mouse button. However, I’m wondering how I can adjust the sprite shown in the screenshot (i.e. apply a different sprite with a different facial expression based on the text) or add additional sprites in the empty space above the text box.

Thank you for the help in advance!

You need to get the Sprite Renderer component from the sprite’s GameObject. The reference for the rendered sprite is SpriteRenderer.sprite so you could do something along the lines of this:

public GameObject spriteGO;
public GameObject newSprite;

void Update() {
	if(Some conditions are met) {
		spriteGO.GetComponent<SpriteRenderer>().sprite = newSprite;
	}
}

I hope that helps!