diff --git a/app/models.py b/app/models.py
index ff0f1f3..d4862aa 100644
--- a/app/models.py
+++ b/app/models.py
@@ -23,7 +23,7 @@ class Customer(Base):
     credit_score = Column(Integer)
     preferred_contact_method = Column(String(20))
 
-    accounts = relationship("Account", back_populates="customer")
+    accounts = relationship("Account", back_populates="customer", cascade="all, delete-orphan")
 
 
 class Account(Base):
@@ -38,7 +38,7 @@ class Account(Base):
     branch_id = Column(Integer)
 
     customer = relationship("Customer", back_populates="accounts")
-    transactions = relationship("Transaction", back_populates="account")
+    transactions = relationship("Transaction", back_populates="account", cascade="all, delete-orphan")
 
 
 class Transaction(Base):