diff --git a/scripts/testSetup.ts b/scripts/testSetup.ts
index 2cf3ea7f79..c3b1762844 100644
--- a/scripts/testSetup.ts
+++ b/scripts/testSetup.ts
@@ -25,7 +25,7 @@ import {
   ParentChain as L1Network,
   ChildChain as L2Network,
   getParentChain as getL1Network,
-  getChain as getL2Network,
+  getChildChain as getL2Network,
   addCustomNetwork,
 } from '../src/lib/dataEntities/networks'
 import { Signer } from 'ethers'
@@ -171,8 +171,8 @@ export const setupNetworks = async (
   }
 
   addCustomNetwork({
-    customL1Network: l1Network,
-    customChainNetwork: l2Network,
+    customParentChain: l1Network,
+    customChildChain: l2Network,
   })
 
   // also register the weth gateway
@@ -245,7 +245,7 @@ export const testSetup = async (): Promise<{
       }
       addCustomNetwork({
         customParentChain: l1Network,
-        customChain: l2Network,
+        customChildChain: l2Network,
       })
       setL1Network = l1Network
       setL2Network = l2Network
diff --git a/src/lib/dataEntities/networks.ts b/src/lib/dataEntities/networks.ts
index 620af314ae..bda1cff8af 100644
--- a/src/lib/dataEntities/networks.ts
+++ b/src/lib/dataEntities/networks.ts
@@ -397,10 +397,10 @@ export const getEthBridgeInformation = async (
 
 export const addCustomNetwork = ({
   customParentChain,
-  customChain,
+  customChildChain,
 }: {
   customParentChain?: ParentChain
-  customChain: ChildChain
+  customChildChain: ChildChain
 }): void => {
   if (customParentChain) {
     if (parentChains[customParentChain.chainID]) {
@@ -416,24 +416,28 @@ export const addCustomNetwork = ({
     }
   }
 
-  if (childChains[customChain.chainID])
-    throw new ArbSdkError(`Network ${customChain.chainID} already included`)
-  else if (!customChain.isCustom) {
+  if (childChains[customChildChain.chainID])
     throw new ArbSdkError(
-      `Custom network ${customChain.chainID} must have isCustom flag set to true`
+      `Network ${customChildChain.chainID} already included`
+    )
+  else if (!customChildChain.isCustom) {
+    throw new ArbSdkError(
+      `Custom network ${customChildChain.chainID} must have isCustom flag set to true`
     )
   }
 
-  childChains[customChain.chainID] = customChain
+  childChains[customChildChain.chainID] = customChildChain
 
-  const parentChainPartnerChain = parentChains[customChain.partnerChainID]
+  const parentChainPartnerChain = parentChains[customChildChain.partnerChainID]
   if (!parentChainPartnerChain)
     throw new ArbSdkError(
-      `Network ${customChain.chainID}'s partner network, ${customChain.partnerChainID}, not recognized`
+      `Network ${customChildChain.chainID}'s partner network, ${customChildChain.partnerChainID}, not recognized`
     )
 
-  if (!parentChainPartnerChain.partnerChainIDs.includes(customChain.chainID)) {
-    parentChainPartnerChain.partnerChainIDs.push(customChain.chainID)
+  if (
+    !parentChainPartnerChain.partnerChainIDs.includes(customChildChain.chainID)
+  ) {
+    parentChainPartnerChain.partnerChainIDs.push(customChildChain.chainID)
   }
 }
 
@@ -495,7 +499,7 @@ export const addDefaultLocalNetwork = (): {
 
   addCustomNetwork({
     customParentChain: defaultLocalParentChain,
-    customChain: defaultLocalChain,
+    customChildChain: defaultLocalChain,
   })
 
   return {
diff --git a/src/lib/inbox/inbox.ts b/src/lib/inbox/inbox.ts
index 71463e3f14..801233d09f 100644
--- a/src/lib/inbox/inbox.ts
+++ b/src/lib/inbox/inbox.ts
@@ -70,7 +70,7 @@ export class InboxTools {
     this.parentChain = parentChains[childChain.partnerChainID]
     if (!this.parentChain)
       throw new ArbSdkError(
-        `ParentChainNetwork not found for chain id: ${childChain.partnerChainID}.`
+        `ParentChain not found for chain id: ${childChain.partnerChainID}.`
       )
   }
 
diff --git a/tests/fork/inbox.test.ts b/tests/fork/inbox.test.ts
index f5b0772019..7ed76a4790 100644
--- a/tests/fork/inbox.test.ts
+++ b/tests/fork/inbox.test.ts
@@ -31,7 +31,7 @@ import { InboxTools } from '../../src'
 import { ethers, network } from 'hardhat'
 import { hexZeroPad } from '@ethersproject/bytes'
 import {
-  ChainNetwork as L2Network,
+  ChildChain as L2Network,
   getChildChain as getL2Network,
 } from '../../src/lib/dataEntities/networks'
 import { solidityKeccak256 } from 'ethers/lib/utils'
diff --git a/tests/integration/sendL2msg.test.ts b/tests/integration/sendL2msg.test.ts
index 2fe9fc62ac..591d4f994c 100644
--- a/tests/integration/sendL2msg.test.ts
+++ b/tests/integration/sendL2msg.test.ts
@@ -21,7 +21,7 @@ import { BigNumber, ethers, Signer } from 'ethers'
 import { InboxTools } from '../../src/lib/inbox/inbox'
 import {
   getChildChain as getL2Network,
-  ChainNetwork as L2Network,
+  ChildChain as L2Network,
 } from '../../src/lib/dataEntities/networks'
 import { testSetup } from '../../scripts/testSetup'
 import { greeter } from './helper/greeter'
diff --git a/tests/integration/testHelpers.ts b/tests/integration/testHelpers.ts
index dc6453590f..dea1b93d19 100644
--- a/tests/integration/testHelpers.ts
+++ b/tests/integration/testHelpers.ts
@@ -31,7 +31,7 @@ import {
   L1ToL2MessageStatus,
   L2ToL1MessageStatus,
 } from '../../src'
-import { ChainNetwork as L2Network } from '../../src/lib/dataEntities/networks'
+import { ChildChain as L2Network } from '../../src/lib/dataEntities/networks'
 import { GasOverrides } from '../../src/lib/message/L1ToL2MessageGasEstimator'
 import { ArbSdkError } from '../../src/lib/dataEntities/errors'
 import { ERC20 } from '../../src/lib/abi/ERC20'