The summer finale of "The Fosters" season 3 is upon us, and it is obviously going to end with a bang. In the penultimate episode of the first half of "The Fosters" season 3 titled "Idyllwild", we saw Brandon and Callie have sex, thinking the latter's adoption is off the table. However, the finale will deal with the repercussions of their hasty decision.

In the previously aired episode, 9, Callie (Maria Mitchell) and her foster brother Brandon (David Lambert) had sex because they had assumed that there is no way Callie to be adopted by Brandon's mothers Stef (Teri Polo) and Lena (Sheri Saum). However, Rita (Rosie O'Donnell), who, Callie saved from false charges, has agreed to recommend her adoption, and so in episode 10, we will see it moving ahead.

And therefore, although Brandon and Callie had initially agreed on announcing their relationship to their mothers, they decide on keeping it a secret. In the promo for "Lucky", Callie is freaking out about having sex with her potential brother, while Brandon remains eerily quiet. It looks like Callie will confess about her and Brandon to the judge during her adoption hearing.

In the promo, she is seen looking tensed and guilty as judge asks, "there is no reason to believe there is anything here, to prevent your adoption.. Is that correct?"

The mothers themselves are having some marital troubles; after Stef confronted Lena about her kiss with Monte (Annika Marks) in episode 9. But they are putting up a united front for the sake of their children; especially Callie. They are also tasked with hosting Lena's parents' 40th anniversary party, which has the potential of reminding them how good they are together, or bring them further apart.

And, as her parents try to save their marriage, Mariana (Cierra Ramirez) tries to repair her relationship with her first serious boyfriend Mat (Jordan Rodrigues).Will she succeed? Find out at 8.00 pm (EST) on Monday, 17 August, when ABC will air season 3 episode 10 of "The Fosters". You can also live stream "Lucky" via ABC Go.