the Tiaki is that little Maori idol???

I wonder if you were thinking of the hei tiki, normally abbreviated to tiki, a ubiquitous Maori fertility image. Other than a pot-belly, the tiki and I have little in common. Now that you know what "kaitiaki" means, it should not be to hard to find a relatively common English name derived from a word roughly synonymous with caretaker. My first name is also a very common surname, but spell it wrong, and you'll have to flee to one of the cities of refuge!