Does touching the buttocks invalidate the wudu?

Question:
He says: Honorable Shaykh, may Allah grant you success. A woman is asking, completing her previous question, saying: Does touching the buttocks directly, specifically a mother touching her child's buttocks, invalidate the wudu, just as touching the front and back private parts does?

Answer:
No, what invalidates the wudu is touching the back private part or the front private part. As for touching the thighs or the buttocks, this does not invalidate the wudu. They say. And this is the private part. Yes.