Dot routing does not work when used in a layout

[AlexandreSi]

Which project does this relate to?

Router

Describe the bug

Hi,

I tried to use the dot routing to nest a page under another page:

In this configuration, I expect that /about/post/author displays the content of the post.author.tsx route component. But it's the content of post.tsx that is displayed.

Your Example Website or App

https://github.com/AlexandreSi/minimal-tanstack-start-project

Steps to Reproduce the Bug or Issue

1. Clone the project
2. Start with npm run dev
3. Navigate to /about/post/author
4. Notice that Post page is displayed instead of Author page

Expected behavior

I expect Author page to be displayed.

Screenshots or Videos

No response

Platform

• Router / Start Version: 1.159.5
• OS: macOS
• Browser: Chrome
• Browser Version: 144.0.7559.133
• Bundler: vite
• Bundler Version: 7.3.1

Additional context

No response