Found this via Lynn on RichmondMommies:
Sunday, May 9 is Mother’s Day and Sunday June 20 is Father’s Day. To celebrate these special days Kings Dominion Season Pass holder’s will receive an amazing Bring-A-Friend discount for their friends and family, ALL Season Pass holder’s can Bring-A-Friend for only $9.99 each! Simply present your 2010 season pass at any ticket window to receive your discounted Bring-A-Friend admission ticket. Limit one ticket per season pass holder. This is one deal you can’t pass up, so don’t miss this chance to bring your mom, dad, or another guest to the park for this great price!