lottalove99's list "Short, Strong Names" of 3 great name ideas: Carl - Calla!

Short, Strong Names

This no-nonsense German variation of Charles is strong and sturdy. A top choice throughout the 20th century, Carl is now verging on falling off the charts.

Carl

Blue suddenly came into the spotlight, as the unusual color name chosen by Beyonce and Jay-Z for their baby girl Blue Ivy. Blue is also a starbaby middle name du jour, used for both sexes in different spellings and forms, from John Travolta and Kelly Preston's Ella Bleu to Alicia Silverstone's Bear Blu. Dave 'The Edge' Evans named his daughter Blue Angel back in 1989.
 Despite all these high profile female references, less than 40 percent of the babies name Blue today are girls. Blue is the heroine of the Marisha Pessl novel Special Topics in Calamity Physics.

Blue

Calla is a botanical name that is much more distinctive than popular Lily or similar Callie. Rarely heard today, it did appear in the popularity lists in the last decades of the nineteenth century.
 
Ultimately from the Greek kallos meaning "beauty", Calla is the name of two separate but similar plants, notably the white calla lily. Given to 130 girls year, it is currently less popular than similar choices such as Kaia, Clara, Cali, Willa, and Calliope, but wouldn't seem out of place among them. 
 Calla is the eponymous heroine of the Rebecca Wells novel The Crowning Glory of Calla Lily Ponder, and there's an English rock band called Her Name is Calla.
 Actress Mare Winningham named her daughter Calla way back in 1987 while sound-alike Cala is an Arabic name meaning fortress.