Personal History in 52 Posts. #1 My Name

As part of Homeschooling, Solace and I just studied a short Story by Alex Haley called "My Furthest Back Person" (it was the inspiration for roots). Then we read another story about finding ancestors and I taight Solace how to search out her own "roots" or family history using familysearch.org. 
We also looked at this cool article on Family Search called "52 questions in 52 Weeks: Writing about Your Life Has Never Been Easier."  Solace and I decided we would take this challenge and answer at least one of these questions per week (due by Friday each week). So, I am beginning now.  Question 1: What is your Full Name? Why Did your Parents Give you that Name?

My full given name (now my "maiden name") is Rebecca Enderton. Now it is legally Rebecca Enderton Johnson. I fell like my parents could better answer this question, but I'll do my best. I know my parents originally wanted to name me Robin. I believe that was the plan up until I was born, but my grandma Shirley did not like it and kept complaining that Robin was a bird not a name. So, in the end they named me Rebecca instead, But I am not sure how they came up with Rebecca from Robin...Mom, Dad, any additional info on that transition?!