Riley—an upbeat, friendly surname name—is red hot for girls and still going strong for boys. If you haven't been spending much time around babies recently, you may be surprised to learn that Riley is the most popular girls' name starting with R and also the Number 1 Irish name for girls in the US.

Riley -- one of the most popular unisex names -- is trendier now for girls though for boys it's a classic, ALWAYS ranking in the US Top 1000.

While some may think of ruby slippers and a yellow brick road, Oz is a legitimate Hebrew name denoting power. An element in a number of names including Ozni, Oziel, and Ozias, it may also be used as a stand-alone choice which may appeal to those who enjoy the likes of Ty, Ed, Bo, and Cy.

Pronounced TEE-bow, this version, which is also a very common surname in France, has a lot more charm than the name it derives from — Theobald. A variant spelling is Thibaut.

For fans of Warren G. All two of them.

If you're looking for a pleasing namesake that's more modern than Darrell/Darryl, this would make an excellent choice. Farrell is an Anglicized form of the Irish Fergal, and was well used as a first name into the nineteenth century, before it faded to mostly surname use.

This more elaborate but not unfamiliar spelling of Riley feels oddly more feminine. Designer and Beatle daughter Stella McCartney has a daughter named Reilley. Still, Reilly or more common Riley is one name that's remained popular for both boys and girls.

Valora may be one of several things: a femininization of word name Valor, celebrating bravery and strength; an Esperanto name meaning "valuable"; a spin on Valerie and Valeria, via the Valorie spelling, meaning "strength, health"; a play on Lora/Laura and Valerie, giving the it the combined meaning of "healthy bay laurel".

This is one of the least known or used of the Theo names, quite possibly because of its last syllable. In Samuel Butler's 1903 novel The Way of All Flesh, there is a clergyman character named Theobald Pontifex.

If Brave isn't enough for you, you might try Braver, which has an even stronger meaning. Braver's -er ending gives it surname style.

Virtually unknown in this country, has an interesting, rhythmic feel.

A strong Indian name used for a character in the series The Legend of Korra.

Riley is the spelling of this lively Irish name most often picked for girls, but this version is occasionally used.

Place-name of a settlement in Galilee in Israel.

Baby-naming rule #984: forget any name that contains the syllable wig.

We can hear the kids teasing him from here.

Farrell is usually considered a boy's name, though the soft sound of this Irish surname makes it perfectly appropriate for a girl, reminiscent of Farrah.

If Theodore has lost its sparkle and Thaddeus feels a bit too serious, you may love the Ethiopian Tadeios. The Amharic version of Biblical Thaddeus has a fun and bouncy sound and comes with the cool nickname "Tad".

Reilly and Riley are hugely popular, but O'Reilly is still an up-and-comer.

Tib was a unisex nickname in the 13th century, used as a short form of Theobald and Isabel. As Theobald waned in popularity, it became far more associated with girls, so much so that Tib was a term for young girls by the 16th century.