The family would not easily show up. When they did, they would conceal their true identity and change their appearance into the form of a man before they wandered around in the mundane world. The people had only heard about the family from tales. None had seen them before.
When Gu Canmo was younger, he managed to make their acquaintance. He even owed the King of the Blue Fox a favor, so he could easily recognize the unique symbol that was worn by every one of his family members.
If Lan Yue were interested in entering Tianju Hall voluntarily, Gu Canmo would not reject his admittance. He even made an exception for him to skip the junior classes and join the intermediate batch. Coincidentally, he happened to be in Lan Waihu's class.
Although Lan Waihu had the same surname as him, she had nothing to do with his family. She was merely an adopted orphan in Yan Chen's family.