How to show sun inside a custom skybox

I am using a custom skybox material with shader as “Skybox/6 Sided”.I have customized the directional light to have the sun effect. I want to show this sun movement in this skybox. The problem is sun is not displayed in this skybox. If I am using the default skybox, which have the shader as “Skybox/Procedural”, then sun is displayed.

So… add a sun. Like you said, the procedural sun won’t show up in a static skybox, so you need to add it yourself. Most people just slap an additive texture on a quad, make it billboard, and call it a day.