It's a good thing that Tara is very, very used to lying. It was pregnancy brain that she didn't remember that he'd not told her about Ginny; of course she's read Harry Potter, but that's not something she'd ever say to Charlie.

"I meant that Thomas and Abel will have a younger sister - you have one, too?" Tara smiles wider, having no issue looking like that's what she meant this whole time. "Ginny's a nice name - how much younger than you is she?"