[javascript] How to select first child with jQuery?

$('div.alldivs :first-child');

Or you can just refer to the id directly:

$('#div1');

As suggested, you might be better of using the child selector:

$('div.alldivs > div:first-child')

If you dont have to use first-child, you could use :first as also suggested, or $('div.alldivs').children(0).