I feel you. It seems some people here don't understand the challenge of distance and grandparents, so neither a table nor discord will do.
Be aware that some dedicated hardware might get obsolete at some point, my dedicated ”Logitech Skype TV cam HD” camera (including WiFi and LAN) only lasted a year until the servers got switched off. And I got dedicated Android cameras which used Duo that got killed, those Chinese devices never really worked well. Therefore I recommend to get a device with a non proprietary protocol, and not requiring manufacturer's servers.
Currently we use tablets on both sides to talk to the grandparents, kids can take it and walk into their own room to show something.
If you are into IT, you could look into Raspberry Pis, could run browser in kiosk mode, then any web video conference software should do, check Jitsi or BigBlueButton.