Any WiFi access point that has an Ethernet port as a backhaul and a secondary Ethernet port as a passthrough (for her laptop) will suffice. Plug the Cat6 you've run into the backhaul connection, and the laptop into the other.
Or, a small Ethernet switch and any WiFi access point that can connect to it from there. Plug everything into it and most modern switches (with auto-uplink detection) will work.
Lots of options, I personally use Nest Routers as they have the passthrough connection I mention, but your choice is endless for such a simple setup.