This website does not use WordPress - it doesn't load any resource with a WP-related name, nor it have any JS or CSS class name relationship (except for .elementor-* CSS classes on some elements in the homepage).
Looking at the bundled JS file, I can say that the page uses, for sure:
It seems that this website is not based on any of the ...
Old question, but a simple way to do this is as follows:
Use a simple timetracker like Kimai v2
Create a "Customer" named after the nursery or childcare provider e.g. "All Day Nursery"
Create Parents as "Projects" by creating a Project for each one against this "Customer". You can use parent names or any ID Number. ...