diff --git a/.changeset/bright-trees-rush.md b/.changeset/bright-trees-rush.md
new file mode 100644
index 0000000..523cce3
--- /dev/null
+++ b/.changeset/bright-trees-rush.md
@@ -0,0 +1,9 @@
+---
+"loglayer": minor
+---
+
+Fix ILogLayer return types
+
+`ILogLayer#withPrefix()` and `ILogLayer#withChild()` were of the incorrect return type. 
+
+Changed to `ILogLayer<ExternalLogger, ErrorType>`.
diff --git a/README.md b/README.md
index a252838..9d901fb 100755
--- a/README.md
+++ b/README.md
@@ -589,7 +589,7 @@ The same log commands would now be formatted as:
 
 ### Child logger
 
-`LogLayer#child()`
+`LogLayer#child(): LogLayer`
 
 You can create a child logger, which will copy the configuration you used for creating the parent, along with the existing context data and plugins.
 
diff --git a/package-lock.json b/package-lock.json
index e881ab1..99a33fe 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "loglayer",
-  "version": "4.3.2",
+  "version": "4.3.3",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "loglayer",
-      "version": "4.3.2",
+      "version": "4.3.3",
       "license": "MIT",
       "devDependencies": {
         "@biomejs/biome": "^1.6.4",
diff --git a/src/MockLogLayer.ts b/src/MockLogLayer.ts
index 4884619..b8fa571 100644
--- a/src/MockLogLayer.ts
+++ b/src/MockLogLayer.ts
@@ -3,7 +3,7 @@
 
 import { MockLogBuilder } from "./MockLogBuilder";
 import type { ErrorOnlyOpts, ILogBuilder, ILogLayer, LogLayerPlugin } from "./types";
-import type { LogLevel, MessageDataType } from "./types/common.types";
+import type { LogLevel, MessageDataType } from "./types";
 
 export class MockLogLayer<ErrorType = Error> implements ILogLayer<any, ErrorType> {
   info(...messages: MessageDataType[]): void {}
@@ -28,11 +28,11 @@ export class MockLogLayer<ErrorType = Error> implements ILogLayer<any, ErrorType
   disablePlugin(id: string) {}
 
   withPrefix(prefix: string) {
-    return new MockLogLayer();
+    return new MockLogLayer() as ILogLayer<any, ErrorType>;
   }
 
   withContext(context: Record<string, any>): ILogLayer<any, ErrorType> {
-    return this;
+    return this as ILogLayer<any, ErrorType>;
   }
 
   withError(error: ErrorType): ILogBuilder {
@@ -56,7 +56,7 @@ export class MockLogLayer<ErrorType = Error> implements ILogLayer<any, ErrorType
   }
 
   child() {
-    return new MockLogLayer();
+    return new MockLogLayer() as ILogLayer<any, ErrorType>;
   }
 
   muteContext() {
diff --git a/src/types/index.ts b/src/types/index.ts
index 8c20bfd..c76d0da 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -67,7 +67,7 @@ export interface ILogLayer<ExternalLogger extends LoggerLibrary = LoggerLibrary,
   /**
    * Calls child() and sets the prefix to be included with every log message.
    */
-  withPrefix(string: string): ILogBuilder;
+  withPrefix(string: string): ILogLayer<ExternalLogger, ErrorType>;
   /**
    * Appends context data which will be included with
    * every log entry.
@@ -106,7 +106,7 @@ export interface ILogLayer<ExternalLogger extends LoggerLibrary = LoggerLibrary,
    *
    * The copied context data is a *shallow copy*.
    */
-  child(): ILogBuilder;
+  child(): ILogLayer<ExternalLogger, ErrorType>;
 
   /**
    * Disables inclusion of context data in the print