Accounts receivable is not told about credit changes for several key customers. Payroll is not told of changes for several employees' benefits. The outside CPA firm is not sent quarterly tax data. Had the father been visiting the Company B son, and shown more interest in what was going on over at Company B other than just its finances, he would have made it much easier for his son to get along with his family in a professional, rather than childish, way. Let gratitude for parents carry the day.
Parents can be difficult, no doubt about it.
This is just how it is between generations. It is nothing new or out of the ordinary. But parents do deserve some grace. Parents, as we all are, are products of their times and are more than likely doing the best they know how. Far too many children of family businesses forget all this.