Can we nest items ?

Hi, props to you for this component!

Is there a way to nest items inside a single virtual list? 
Having parents/children, so if with : 

**Parent 1**
 - Child 1
 - ...
  - Child 10
  
  **Parent 2**
  - Child 1
  - ...
  - Child 500

Parent 1 gets fully rendered and Parent 2 would only render 18 children (assuming we keep 30 items in the DOM)

Thanks in avance!