Custom Menus Help Needed

Under Appearances>Menus

I have created a category menu listing all the Top Level Parent categories, I then have used widgets to place that menu on my homepage

So it looks like

Beauty and Style
Business and Finance

Not I have Child Subcategories below each of those parent ones, and I want those to be seen when a person clicks on a parent and goes through to that category.. So for instance if a user is on my homepage and they click on Beauty and style it takes them to

mydomain.com/category/beauty-and-style

Now on the right hand side i want to display Beauty and Styles Child categories

So i have created tha menu, but I dont have a widget for the sidebar for that category. So is there a manual way I can have it appear there???