'The Fosters' season 4 episode 16 spoilers: Stef's mom gets engaged; Emma discovers Jesus' secret

A promotional photo of Freeform's TV series "The Fosters." | Facebook/TheFostersTV

A declaration of love is made on the upcoming episode of Freeform's family drama "The Fosters" season 4.

Titled "The Long Haul," the show's next episode will see Stef's (Teri Polo) mom make a special announcement. According to the official synopsis, Stef's mom, Sharon (guest stars Annie Potts), and her boyfriend, Will (guest star Rob Morrow), head back to the Adams–Foster house with news of their engagement. The whole family happily prepares for the wedding ceremony, but Stef later discovers that her mom is having second thoughts about tying the knot once again.

Meanwhile, Emma (Amanda Leighton) will stop at nothing to come clean with Jesus (Noah Centineo). Emma tries to make peace by writing him a letter, only to learn that he is keeping a dark secret of his own. Lena (Sherri Saum) organizes an LGBTQ-friendly sex ed class for students, but instead of being beneficial to Jude (Hayden Byerly), her initiative leads the other students to tease her son.

In the latest episode, one of the highlights of the story is the conflict between Brandon (David Lambert) and Jesus. Despite telling Mariana (Cierra Ramirez) early on in the hour that the pregnancy test's result was negative, Emma admitted to Brandon that she is indeed a few weeks pregnant. She decided not to tell Jesus because of what he's going through, so she revealed the truth to his brother instead. The hour wrapped up with Emma not being able to tell Jesus about her situation.

Earlier this month, Centineo spoke with TV Guide, and he shared that Jesus' short fuse caused by his head injury will test the family's relationship in the coming episodes. "It's a lot of strain on the relationships. You have someone who is emotionally unstable," he explained. "It's a huge test of how much your family members are willing to withstand and take before they snap at you, or they break, or they can't handle you. They could walk away and leave you to handle yourself. It really tests the bond between family members," the actor added.

The fourth season of "The Fosters" airs every Tuesday night at 8 p.m. ET on Freeform.