Professional charges can be paid to directors relatives

Yes. Professional charges can be paid to the relatives of the directors. But it has to be within the perview of sec. 40A(2)b of The IT Act. As per sec 40A(2)b:

The expenses for which payment has been made to a relative or a person with substantial interest shall be disallowed when –

• These expenses are incurred for goods, services or facilities.
• Payment has been made to a relative or a person with substantial interest as defined above.
• Such expenses are excessive or unreasonable. They are not in line with fair market value. Or they may not be a legitimate need of your business & profession. Or when you have incurred these expenses and they result in a benefit to you. Do note that an Assessing Officer can disallow expenses when they are not in sync with the needs of your business, even though these may have been paid as per the market value.