I have created a behaviour subject in a service class.
public personObject: BehaviorSubject = new BehaviorSubject({
I forgot to mention that I was using I was using ViewContainerRef to create a sibling component and it turns out behavior subject does not work the same way with component created using ViewContainerRef.
Other wise Behaviour subjects of any object work exactly like with number or string. I used @Input to send data to component for now.