Computers running in stealth mode: can they be seen from within a home network?

Hi there,

I was wondering whether there is way/setup that would prevent two computers running Comodo Firewall in stealth mode, to communicate with each other while they are connected to the same home network via a router.

Currently, the two computers are trying to connect to each other every 30 min or so, as shown by the two Firewall Events loggers.