I'm so sorry for your lost. 😞 If you want the Roku under your own account you will need to factory reset the Roku, either through the menu:
Settings> system> advance system settings> factory reset> follow prompts
Or by finding the reset button or pinhole on the Roku itself, press it with Roku power for at least 30 seconds.
After a reset you might have pair your remote to the Roku.
Edmund
Roku Community Streaming Expert
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