Is the divorce of a son from his wife, under the duress of his father threatening to divorce the mother, considered a valid and Islamically sound divorce, or does it not take effect?

Obedience to parents is not obligatory in divorcing one's wife, unless there is a legitimate Shariah reason necessitating the divorce, because obedience to them is only in what is good and permissible. So, if the father requests the divorce of the wife for a legitimate Shariah reason, such as her moral corruption, then obedience becomes obligatory; otherwise, it does not, especially if she is upright in her religion and character. If the husband utters the divorce, it takes effect, even if his intention was to please his parents. If the verbal divorce is the first or second, the husband may reconcile with his wife during her waiting period (iddah). However, if the waiting period ends, she cannot return to him except through a new marriage contract.