Where is your router located in your home? Connecting your Roku devices through ethernet would be a great solution, but can present challenges if you have to run long lengths of ethernet throughout the house. I would recommend an option that has worked wonderfully for me: Use a pair of powerline adaptors to connect your streaming device directly to your router using your home's electrical wiring. These can be picked up fairly inexpensively at any major electronics store (ie. Microcenter) or on Amazon.
If that doesn't sound like a good option, you could also try setting up a Wi-Fi access point (or extender) in-between your router and the living room in order to boost/extend your wireless signal.
I hope that this helps. Good luck and let us know how it goes.
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