Sharing calendar between family members

Hello everyone.
I am trying to move away from Google’s Calendar.
On Google we each have our own calendars which we have shared with each other (Edit/Delete access).
We very often create events in each others calendars.
To indicate that we both participate in an event we invite eachother.

We have tried to reproduce this setup in nextcloud but it does not appear to be working at all.
When i add her to a calander as a participant nothing happens.

Is there a way to reproduce this setup?

Maybe this video helps

I have setup sharing and viewing each others calendars are working.

However the invitation function does not.
It seems that if i invite someone that i share the calendar with then nothing happens.