Family Sharing not working

Make sure you are doing everything exactly as Apple directs:

Click on this link to learn how to 'Set up Family Sharing' --> Set up Family Sharing - Apple Support

Read the section: "Invite people to join your family"

For example, I don't see anything about text messages, and it certainly should be possible to do using an Internet connection.

You don't mention you daughter's age. How things behave will vary greatly depending upon if you daughter is 6 or 60.

Have you tried simply signing out of your accounts and signing back in? Same for simply restarting the devices?

If you still have questions or problems:

Contact Apple. Click here --> Choose your country or region - Official Apple Support Select your country, then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.

or:

Contact Apple for support and service --> "See a list of Apple phone numbers around the world."

Click here --> Contact Apple for support and service - Apple Support

These things mostly have to do with the settings on a particular Apple ID, not any particular hardware. A new phone should not make any difference. Is she using the same ID (if she has any purchases that is particularly important)?

Depending upon the country she would not necessarily have to have a child-labeled account now but it would probably be a good idea to keep parental controls entered on her phone until you are ready to cut some apron strings.

Also have a look at:

Help your child set up an iPhone, iPad, or iPod touch - Apple Support