Shared library defaults

Hello, I have set up library sharing with my wife. I'm transferred to my wife iPhone and iPad work but any photos I take on her machines do not synchronise into iCloud photos and to my iPhone..

I have made sure all machines iPads iPhones, imac are up-to-date with the latest iOS, I have used the 'shared library' drop down from photos to create a shared library, all photos from my iCloud library can be seen on my wife's iPad.but any new ones taken on my iPhone do not appear on her iPad unless put unshared library.

They are shared when I manually select each photo to 'shared library' and the symbol of two people shows.

So, the question is how can I make sure any new photos which are taken on any machine on my network are put into the shared library automatically.

thanks

eric