A vehicle seatbelt monitoring system for monitoring seatbelts of a plurality of seats comprising: i) a buckle sensor for each seat configured to determine whether a seatbelt is buckled into a buckle attachment of each seat; ii) a seatbelt webbing payout sensor for each seat configured to determine an amount of seatbelt webbing that is unwound from a seatbelt retractor associated with each seat; and iii) a seatbelt monitor control module coupled to the buckle sensor and the seatbelt webbing payout sensor and configured to receive buckle state data from the buckle sensor for each seat and seatbelt payout data from the seatbelt webbing payout sensor for each seat. The seatbelt monitor control module is further configured to determine if a first seatbelt is unbuckled or not properly worn and, if so, to determine if a second seatbelt is buckled or properly worn when the first seatbelt is unbuckled or not properly worn.