Please forgive me my ignorance but I am new in Angular. 
Was googling how to make a sidebar navigation component with multi-child nodes. 
Obviously, everything is driven by JSON so we don't know how many child nodes there will be. 

I can see that it's a difficult matter to monitor the state of each menu item with child nodes which can also have multiple children with children of their own :)

Looked into templates to see how other pros are doing it and that they using a single drop-down menu or using jquery: 
<https://genesisui.com/demo/?template=prime&version=1.8.14&framework=bootstrap4-angular5>

Is there a reason why devs are going with jquery? Seems like a little bit of overkill for few small functionalities.

Can you point me in the right direction of multi-level drop-down sidebar nav component done well?

**Should you use jquery in Angular App?** 

\*I know this is a super long question/s