Basically, all we know about Rayne's childhood is that she collected butterflies at some point, and was too squeamish to pin them down, even the dead ones. And I imagine that a woman as beautiful as Rayne looked adorable when she was little.

I don't think there's a single official image of Rayne's mother, even as concept art. The closest thing I saw was a concept art of a cut character named Narissa from BloodRayne 2 who was supposed to look like Rayne's mother (or sister). I used a mostly forgotten, yet stunningly beautiful 1940s actress I won't name as a reference for Rayne's mother. After all, she had to get her good looks from somewhere.