Adding Health Check to DTH for Child Device?

I was reading through this: Device Health for third party handlers? which pretty much says health check isn’t fully supported but you can reverse engineer other devices and figure it out. That’s all fine and dandy but what if you have a child device? I can’t exactly ping the device so is there any way to tell if the child device hasn’t received a update for say 2 hours?

I have added a last update attribute:

attribute “lastCheckin”, “String”

And added that to a multitile so when the device gets updated so does the display. This works fine but you have to go into the device to see it. I would like the standard health check red exclamation point on the main device list so I know if a value hasn’t been updated for a while. Example: Parent device gets kicked off the network and can’t send updates to the child devices. Child devices stick with last known value. I would love to be able to mark it as unhealthy so I can check on it.

I was looking at runEvery1Hour(). Would that be good for this? Is there something like that for a device where I could just keep a counter and if my last update time is older then current + counter then my data is stale?