I was under the impression that once set up, these could be placed in various locations. But does the "main one" need to be connected to my wireless router at all times?

I'm using the TP-Link AC1750 A7 for the router, bridged with my veriozon wireless mifi 7730l through my desktop compter.

I was hoping the connection to the router could be wireless and therefore be able to utilize the range of the router to extend the range of the 3 pods. (does that make sense?)