His sparkling blue eyes seemed relentlessly cheerful to me.

Disney staff members were everywhere, as they had been at the airport, relentlessly cheerful and very efficient at people moving.

And I don't actually worry much for I'm programmed to be relentlessly cheerful.

The park is relentlessly cheerful, and almost eerily tranquil.

Only one creature I knew had a voice as squeakily high and relentlessly cheerful as that.

But she said she also aimed to make her audience relax, and the tone of the show is relentlessly cheerful.

You're always part of a crowd in Bangkok, but your fellows will be relentlessly cheerful.

However, the term actually has a broader use in practice: sunshine pop can sound relentlessly cheerful, but also more subdued or even sad.

Mary was relentlessly cheerful, and she loped rather than walked.

Connors was relentlessly cheerful, as if he dared not show anything but good humor.