The decision to send Wei Qingwan back to the villa was from Wei Mingting and Wei Yichen, not from Yun. Today Yun is bringing her to Madam Yuan's mid-autumn banquet without prior notice to them.
Initially, Yun just planned to bring Wei Qingwan back home for the two days of the Mid-Autumn Festival, and then send her back to the villa.
She could later tell her husband that it was just to celebrate the Mid-Autumn Festival together. As the wife and mother, wanting her daughter by her side was understandable, considering her husband and eldest son were not around. She believed her husband wouldn't make a big deal of it due to his character.
But if Wei Ruo delivers the news, the nature might change.
Not to mention Wei Ruo's words would make her seem secretive, the situation might get twisted if told through Wei Ruo.
She and her husband still had unresolved issues from their last argument.
She regretted losing her temper that day, and after calming down, she realized her impulsiveness.