The Ping Reboot function periodically sends Ping commands to a specified IP address and wait for received responses. If no response is received, the device will send Ping commands a defined number of times at a defined frequency. If no response is received after the defined number of unsuccessful retries, the device will commit the specified action (reboot, by default).
Wget is a computer program that retrieves content from web servers. The Wget Reboot function works in a very similar manner to Ping Reboot. While Ping Reboot sends ping requests to determine whether the conditions for the specified action have been met, Wget Reboot attempts to retrieve the contents of a web server.
Wget and Ping Reboot works in very similar fashion and can be configured exactly same way. You could monitor device connected to your router using ping reboot by configuring everything exactly the same way as wget reboot. Just make sure to insert correct device LAN IP address in Hosts to ping field while configuring.