We are getting married next year, and are paying for most of the wedding ourselves. We had a location picked out for the rehearsal dinner that we both really wanted. If we were to use this location, then our venue for the reception, a sister property of the rehearsal dinner restaurant, would lower our required price per head by $15. Then my mother offered to pay for the rehearsal dinner. This was very generous however my mom and stepfather can't afford to pay for the rehearsal dinner where we wanted it. She being the mother of the groom, would it be rude to ask her if she would mind if we paid the difference? I don't want to offend my mom but we were all set to book this place and now are in limbo merely out of guilt.