How to setup rewrite on IIS for child application?

Question

IIS

In general, the point is this. There is an IIS server that hosts CRM Dynamisc, and there is also a web application that is hosted as a child.
Structure of IIS:
- Site with CRM Dynamics
- folders and files
- child application

Let's say we open a child application, then always at the end of the URL according to the routing logs is appended at the end of the URL /default.aspx.
Link example:

http://CRM Dynamics site/child application/section?setting=123456 /default.aspx

How to remove /default.aspx before IIS sends request to child.
PS Please do not throw stones, I am not at all special in setting up IIS, so I ask for help)

Upd
I tried to prescribe the URL Rewrite rule in my daughter:

Pattern: (*.?)/?Default\.aspx$
IgnoreCase: true
Action Type: Rewrite
Rewrite URL: {R:1}
Append query string: true

But it didn't work