Magento 2 Parent's theme styles are not loading in the child theme

Question

I have create a child theme that extends from magento-luma theme by following the steps below:

app/design/frontend/Company/parent/registration.php

<?php

\Magento\Framework\Component\ComponentRegistrar::register(
    \Magento\Framework\Component\ComponentRegistrar::THEME,
    'frontend/Company/parent',
    __DIR__
);

app/design/frontend/Company/parent/theme.xml

<theme xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Config/etc/theme.xsd">
    <title>Parent Theme</title>
    <parent>Magento/luma</parent>
</theme>

app/design/frontend/Company/parent/web/css/source/_extend.less

body{
  background-color: red;
}

After activating this theme from from magento admin. it works fine, load parent luma styles , images and js perfectly. When I make another child theme that extends with the parent theme created above. It does not load the its parent themes styles and all other static assets.

I created the grand-child theme as follows.

app/design/frontend/Company/child/registration.php

\Magento\Framework\Component\ComponentRegistrar::register(
    \Magento\Framework\Component\ComponentRegistrar::THEME,
    'frontend/Company/child',
    __DIR__
);

app/design/frontend/Company/child/theme.xml

<theme xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Config/etc/theme.xsd">
    <title>Child Theme</title>
    <parent>Company/parent</parent>
</theme>

app/design/frontend/Company/child/web/css/source/_extend.less

body{
  color: yellow;
}