You can pass your clicked element by dataadd(this)
;
You may wonder how this
comes inside the method. adding this
keyword like above will refer to the current element.
Then using that element, you can find children and with each
you can grab other details by loop through the children.
function dataadd(ele){
var children = $(ele).find('div');
children.each(function(idx, element){
console.log($(element).attr('id'));
});
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="big" onclick="dataadd(this)">
<div id="a">child1</div>
<div id="b">child2</div>
</div>