The family members are about to hear why Nick is going on a vengeance spree on the next episode of The Fosters.

After the school went on lock-down, the Foster family goes back to the house in a sneak peek released on Tuesday. Jesus is questionable about what's going on with Nick and if he really did have a gun. Stef says they don't know that for sure, but it would make sense since his father owns a gun and now it's missing.

Jesus doesn't take that as a sign that Nick took the gun though, but Mariana chimes in on how that wouldn't be too surprising. After all, he's the one who burned down the warehouse. The twins go at it for a bit, but Stef wants everyone to try to get along since their lives are kind of in danger.

So Mariana tells everyone that she talked to Nick about why he would be upset. She reveals that he saw her with Mat in the garage where a misunderstanding took place. Mat said he wanted to get back together with Mariana, but she didn't want to hurt Nick so they kissed goodbye. Unfortunately, Nick saw this and obviously took it the wrong way.

In fact, this doesn't make any sense to Jesus either. He asks why they would kiss goodbye, but Mariana tells him that she told Nick she wasn't getting back together with Mat, but he didn't believe her. Jesus pretty much feels the same way.

He tells her that the way his sister ran into Mat's arms doesn't exactly qualify for no feelings being there, but the family isn't in a good place to argue. What's done is done and now they just have to deal with what comes next.

Check out the scene below.

The Fosters airs on Mondays at 8 p.m. ET on Freeform.