The McQueens aren't letting Myra's court date get them down - it's party time for the family with Michaela's 21st and the Diamond Jubilee celebrations. Lynsey and Riley are also at the party and they struggle with how to tell Mercedes about their relationship. Mercedes finally turns over a new leaf, but when a drunk Mitzeee drops a bombshell, can her positive outlook survive this devastating news? Meanwhile, Ste and Doug deliver a cake to the celebration as well as the news that they are a couple. Later, the McQueens are sent into disarray when Bart returns from court with some devastating news...