Jealous

First of all, she was very pleased with the way Muyang was including himself in the family. He kept saying, 'we and 'us'' which brought a smile to her face. This clearly meant that he fully accepted her family as his. She was happy because he was protecting them just as much as he protected her. 

If it had not been for him, she would not have known that her mother was suffering again at the hands of that wicked woman.

However, it was Christmas and she did not want to spend her Christmas worrying about what may or may not happen. She was incredibly grateful for his heads up, in case the Wang's showed up she would give her brothers a heads up so that they did not simply jump into their arms and offer everything up to them on a silver platter.

Besides, there was no conclusive evidence that the Wang's were related to her mother. If the DNA results were here she would know but right now, she was operating on theories.