Parent Value is Null on Init

[Arpit1496]

I want a custom Validator which based on presense of some key in group, affects the "enabled" flag of other keys of the same group.
For that I want to use control.parent value but it is NULL when the form is initialised and validators are run for the first time.

Once some field is clicked or tapped, the parent is initialised for the subsequent vlidator calls.

But I want first time parent to be initialized as well. How can I do that ?

This is my sample:

In the below: if "isNull" flag is true, I want the form to be disabled from init.