diff --git a/app/models/session.py b/app/models/session.py
index 900c8e7..3c59e58 100644
--- a/app/models/session.py
+++ b/app/models/session.py
@@ -10,9 +10,9 @@ class Session(db.Model):
     name: Mapped[str] = mapped_column(unique=True)
 
     authorized: Mapped[bool]
-    users: Mapped[List[User]] = relationship("User", back_populates="session")
+    users: Mapped[List[User]] = relationship("User", cascade="all, delete-orphan", back_populates="session")
 
-    tasks: Mapped[List[Task]] = relationship("Task", back_populates="session")
+    tasks: Mapped[List[Task]] = relationship("Task", cascade="all, delete-orphan", back_populates="session")
 
     def has_depending_tasks(self):
         tasks = Task.query \