Merge commit '9b0050e9aabe4be65c78ccf292a348f309d50ccd' as 'docs'

```
git subtree add --prefix=docs/ https://github.com/gohugoio/hugoDocs.git master --squash
```

Closes #11925

docs/content/en/methods/shortcode/Parent.md

@@ -0,0 +1,50 @@
+---
+title: Parent
+description:  Returns the parent shortcode context in nested shortcodes.
+categories: []
+keywords: []
+action:
+  related: []
+  returnType: hugolib.ShortcodeWithPage
+  signatures: [SHORTCODE.Parent]
+---
+
+This is useful for inheritance of common shortcode parameters from the root.
+
+In this contrived example, the "greeting" shortcode is the parent, and the "now" shortcode is child.
+
+{{< code file=content/welcome.md lang=md >}}
+{{</* greeting dateFormat="Jan 2, 2006" */>}}
+Welcome. Today is {{</* now */>}}.
+{{</* /greeting */>}}
+{{< /code >}}
+
+{{< code file=layouts/shortcodes/greeting.html  >}}
+<div class="greeting">
+  {{ trim .Inner "\r\n" | .Page.RenderString }}
+</div>
+{{< /code >}}
+
+{{< code file=layouts/shortcodes/now.html  >}}
+{{- $dateFormat := "January 2, 2006 15:04:05" }}
+
+{{- with .Params }}
+  {{- with .dateFormat }}
+    {{- $dateFormat = . }}
+  {{- end }}
+{{- else }}
+  {{- with .Parent.Params }}
+    {{- with .dateFormat }}
+      {{- $dateFormat = . }}
+    {{- end }}
+  {{- end }}
+{{- end }}
+
+{{- now | time.Format $dateFormat -}}
+{{< /code >}}
+
+The "now" shortcode formats the current time using:
+
+1. The `dateFormat` parameter passed to the "now" shortcode, if present
+2. The `dateFormat` parameter passed to the "greeting" shortcode, if present
+3. The default layout string defined at the top of the shortcode