How to choose random children

I have following Problem:
I have no clue how I let JavaScript delete a random Child.
I have a DIV (gets randomly chosen). In this DIV are more DIVs and I want a JavaScript function that deletes one or two DIVs. But there is one DIV in there that shouldn't be deleted. For now I have this:

if (spieleranzahl == 4) {
    var del = document.getElementById(random)
    if(del.hasChildNodes()){
        let rdm = Math.floor(Math.random() * 4); 
        del.removeChild(del.childNodes[rdm]);
    }
    if(del.hasChildNodes()){
        let mdr = Math.floor(Math.random()* 3); 
        del.removeChild(del.childNodes[mdr]);
    }
}

thanks for Answers.

You could use the :nth-child selector to get yourself a random child.

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

document.querySelector('.btn').onclick = () => {
  let parentSelector = document.querySelector('.parent');
  // we want to make sure we get a random number between 1 and the number of child.
  let random = Math.floor(1 + Math.random() * parentSelector.childElementCount);
  child = document.querySelector('.parent>span:nth-child(' + random + ')');
  if(child) {
    console.log(child);
    child.remove();
  }
}

<!-- language: lang-html -->

<div class="parent">
  <span>child #1</span>
  <span>child #2</span>
  <span>child #3</span>
  <span>child #4</span>
  <span>child #5</span>
  <span>child #6</span>
  <span>child #7</span>
</div>

<button class="btn">Delete a child !</button>

<!-- end snippet -->

I Understand from your question that you need to remove two elements at a time, leaving only the last element

<script>
function remove(){
  var elements = document.getElementsByClassName('parent')[0].children;
  if(elements.length  == 1)
  	return;
  
  elements[getRandom(elements.length-1)].remove();
  if(elements.length > 1){
  	elements[getRandom(elements.length-1)].remove();
  }
}

function getRandom(max){
	return Math.floor(Math.random() * (max - 0 + 1)) + 0;
}

</script>

<div>1</div>
<div>2</div>
<div>3</div>
<div>4</div>
<div>5</div>
<button onclick="remove();" >Remove</button>

Using randojs.com, you can accomplish this like so:

var randomDivChild = rando(document.querySelectorAll('.parent>div'));
if(randomDivChild) randomDivChild.remove();

Nothing else needed. Check out the site for documentation if needed, but it's pretty straightforward.