Script goof

When Vanessa is trying to make Mona feel better, she says "want me to scratch your back? My mom always used to do that for me" do then when Mona lays on her lap she immediately says "Ruby said there's a good chance you're gonna win."

Why in the same 15 seconds did she refer to ruby as mom, and then ruby? Is this a script goof, actor goof, that somehow noone picked up on? She never called her ruby any other time. And was made to be believe ruby was her birth mom. I'm so surprised this got by without being changed. Did anyone else notice this?