diff --git a/src/database/keyvalue.rs b/src/database/keyvalue.rs
index 80fdfb31..fb285322 100644
--- a/src/database/keyvalue.rs
+++ b/src/database/keyvalue.rs
@@ -646,7 +646,7 @@ mod test {
         assert_eq!(tree.get_last_index(ScriptType::Internal).unwrap(), None);
 
         let res = tree.increment_last_index(ScriptType::External).unwrap();
-        assert_eq!(res, 1337);
+        assert_eq!(res, 1338);
         let res = tree.increment_last_index(ScriptType::Internal).unwrap();
         assert_eq!(res, 0);
 
@@ -654,7 +654,7 @@ mod test {
             tree.get_last_index(ScriptType::External).unwrap(),
             Some(1338)
         );
-        assert_eq!(tree.get_last_index(ScriptType::Internal).unwrap(), Some(1));
+        assert_eq!(tree.get_last_index(ScriptType::Internal).unwrap(), Some(0));
     }
 
     // TODO: more tests...
diff --git a/src/descriptor/extended_key.rs b/src/descriptor/extended_key.rs
index 9e6fc10a..71347f16 100644
--- a/src/descriptor/extended_key.rs
+++ b/src/descriptor/extended_key.rs
@@ -59,6 +59,14 @@ impl DescriptorExtendedKey {
             let path_as_vec: Vec<ChildNumber> = path.clone().into();
             final_path.extend_from_slice(&path_as_vec);
         }
+        let our_path: Vec<ChildNumber> = self.path_with_index(index).into();
+        final_path.extend_from_slice(&our_path);
+
+        final_path.into()
+    }
+
+    pub fn path_with_index(&self, index: u32) -> DerivationPath {
+        let mut final_path: Vec<ChildNumber> = Vec::new();
         let our_path: Vec<ChildNumber> = self.path.clone().into();
         final_path.extend_from_slice(&our_path);
         let other_path: Vec<ChildNumber> = self.final_index.as_path(index).into();
@@ -67,6 +75,7 @@ impl DescriptorExtendedKey {
         final_path.into()
     }
 
+
     pub fn derive<C: secp256k1::Verification + secp256k1::Signing>(
         &self,
         ctx: &secp256k1::Secp256k1<C>,
@@ -81,10 +90,10 @@ impl DescriptorExtendedKey {
         index: u32,
     ) -> Result<ExtendedPubKey, super::Error> {
         if let Some(xprv) = self.secret {
-            let derive_priv = xprv.derive_priv(ctx, &self.full_path(index))?;
+            let derive_priv = xprv.derive_priv(ctx, &self.path_with_index(index))?;
             Ok(ExtendedPubKey::from_private(ctx, &derive_priv))
         } else {
-            Ok(self.pubkey.derive_pub(ctx, &self.full_path(index))?)
+            Ok(self.pubkey.derive_pub(ctx, &self.path_with_index(index))?)
         }
     }
 
diff --git a/src/descriptor/mod.rs b/src/descriptor/mod.rs
index bca3ddd7..ac241b53 100644
--- a/src/descriptor/mod.rs
+++ b/src/descriptor/mod.rs
@@ -479,7 +479,7 @@ mod test {
                 .to_string(),
             "mqwpxxvfv3QbM8PU8uBx2jaNt9btQqvQNx"
         );
-        assert_eq!(desc.get_secret_keys().len(), 1);
+        assert_eq!(desc.get_secret_keys().into_iter().collect::<Vec<_>>().len(), 1);
     }
 
     #[test]
@@ -503,7 +503,7 @@ mod test {
                 .to_string(),
             "mqwpxxvfv3QbM8PU8uBx2jaNt9btQqvQNx"
         );
-        assert_eq!(desc.get_secret_keys().len(), 0);
+        assert_eq!(desc.get_secret_keys().into_iter().collect::<Vec<_>>().len(), 0);
     }
 
     #[test]
@@ -527,7 +527,7 @@ mod test {
                 .to_string(),
             "mhtuS1QaEV4HPcK4bWk4Wvpd64SUjiC5Zt"
         );
-        assert_eq!(desc.get_xprv().len(), 0);
+        assert_eq!(desc.get_xprv().into_iter().collect::<Vec<_>>().len(), 0);
     }
 
     #[test]