Filter in array or empty

Hey,

i try to filter pages by a field wich is either empty or contains a key from a array

$selection = $all->children()->filterBy('target','in',$myArray);

This works… but i also need all children where the target field is empty.
How can i do this?

Greetings
David

$myArray = ['', 'a', 'b', 'c'];

Add an empty value to your array.

Thanks @texnixe.