Rebecca is a lovely name. (I like the spelling 'Rebekah', too).
Rebecca Violet is simply adorable. It's a lovely combo and not too girly at all. It's very feminine, but nothing to worry about.
Here are some more suggestions:
Rebecca Elizabeth
Rebecca Jane
Rebecca Laura
Rebecca Lynn
Rebecca Victoria
Rebecca Kate
Rebecca Catherine
Rebecca Ingrid
Rebecca Faith
Rebecca Olivia
Rebecca Blythe
Rebecca Cecilia
Rebecca Caroline
Rebecca Gretchen
Rebecca Margaret
Rebecca Olive
Rebecca Sarah
Rebecca Niamh
Rebecca Rose
Rebecca Willow
Rebecca Eleanor
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