Possible, yes. As others mentioned, wired is always better, but you could use the 2nd router (assuming it has the necessary functionality/options) in wireless bridge mode to accomplish what you want.
You may also be able to use MOCA adapters instead of a wireless bridge, depending on your needs. MOCA would connect an ethernet port on each router into a nearby coax jack in your home, and then you can bridge the second router that way without needing to do the bridge wirelessly.
Possible, yes. As others mentioned, wired is always better, but you could use the 2nd router (assuming it has the necessary functionality/options) in wireless bridge mode to accomplish what you want.
You may also be able to use MOCA adapters instead of a wireless bridge, depending on your needs. MOCA would connect an ethernet port on each router into a nearby coax jack in your home, and then you can bridge the second router that way without needing to do the bridge wirelessly.