Family link and Google home

[zachthebomb13]

I now have three Google home devices, and would like to register my kid's family link accounts to them. According to the Google website, you register them using their special device that you've set up. https://support.google.com/families/answer/7521263?hl=en

My issue is that I don't have an extra device to use to set up the Google homes. Anyone know how I can do this without their device? Thanks!