Older, more calm and mature Dinah would have given a disapproving look then offered Roy help if he ever needed it. Any version of Dinah knew that Roy wouldn't put Lian in danger, even if it was her own mother who posed it. Older, more mature Dinah understood and trusted Roy do what was best for himself and for Lian.
Teenage Dinah, however, was not so graceful or accepting of situations she didn't like.
"Yes! That's absolutely what you were supposed to do. Cheshire gave up 'just popping in for hugs' rights when she left Lian with you. Why? Because she knew that being around Lian would put her in danger." Scowling, Dinah managed to clamp down on the angry teenage hormones before they did anymore damage, "Hang on. Give me a second." She said, pressing her hand to her eyes and closing them tightly, taking a few deep breaths and counting to ten.
Being a teenager again really sucked.
"Okay..."She said, more calmly and dropped her hand from her face, "Okay so... disregard everything I just said, okay? I know you're not going to put Lian in danger. I just don't trust her. That's all, end of story. Do you want something to drink?" Hopefully they could be done with this conversation- at least for now. At least until this age business was over and she could talk to Roy like a real adult instead of as a temperamental teen. And then she could say she was sorry for bursting in and calling him crazy and picking a fight... but the odds of that happening today were pretty slim. Teenagers weren't known for their skills at apologies.