Declan is the Anglicized form of the Irish name Deaglán. St. Declan was one of the first missionaries to bring Christianity to Ireland, preceding St. Patrick. Originally from Wales, he founded the monastery of Ardmore in Ireland.

Sierra is a name borrowed from the western mountain range, with Latin rhythm and cowboy charm, that has led to many offshoots: Cierra, Cyara, and so on. It is now probably past its peak but retains its pretty-yet-strong sound. The meaning refers to the sharp, irregular peaks of some of the Western mountains such as the Sierra Nevada.

Harley in a dress.