Access $parent's $parent in knockout view - nesting context

Use the $parents array, the grandparent would be $parents[1]. You may also be able to use $root if the grandParent object in your example is the topmost parent.

From the docs:

$parents

This is an array representing all of the parent view models:

$parents[0] is the view model from the parent context (i.e., it’s the same as $parent)

$parents[1] is the view model from the grandparent context

$parents[2] is the view model from the great-grandparent context

… and so on.

$root

This is the main view model object in the root context, i.e., the topmost parent context. It’s usually the object that was passed to ko.applyBindings. It is equivalent to $parents[$parents.length - 1].

You can use $parentContext.$parent.

$parentContext provide many useful properties such as ($data, $parent, $index, ...)