diff --git a/rules/type-declaration/src/TypeInferer/ReturnTypeInferer.php b/rules/type-declaration/src/TypeInferer/ReturnTypeInferer.php
index 212d0c2638f..ca850a751ad 100644
--- a/rules/type-declaration/src/TypeInferer/ReturnTypeInferer.php
+++ b/rules/type-declaration/src/TypeInferer/ReturnTypeInferer.php
@@ -53,9 +53,12 @@ final class ReturnTypeInferer extends AbstractPriorityAwareTypeInferer
             $type = $this->typeNormalizer->uniqueateConstantArrayType($type);
             $type = $this->typeNormalizer->normalizeArrayOfUnionToUnionArray($type);
 
-            if (! $type instanceof MixedType) {
-                return $type;
+            // in case of void, check return type of children methods
+            if ($type instanceof MixedType) {
+                continue;
             }
+
+            return $type;
         }
 
         return new MixedType();
diff --git a/rules/type-declaration/src/TypeInferer/ReturnTypeInferer/ReturnedNodesReturnTypeInferer.php b/rules/type-declaration/src/TypeInferer/ReturnTypeInferer/ReturnedNodesReturnTypeInferer.php
index 263d707d020..99300f2ed7b 100644
--- a/rules/type-declaration/src/TypeInferer/ReturnTypeInferer/ReturnedNodesReturnTypeInferer.php
+++ b/rules/type-declaration/src/TypeInferer/ReturnTypeInferer/ReturnedNodesReturnTypeInferer.php
@@ -8,6 +8,7 @@ use PhpParser\Node;
 use PhpParser\Node\Expr\Closure;
 use PhpParser\Node\FunctionLike;
 use PhpParser\Node\Stmt\Class_;
+use PhpParser\Node\Stmt\ClassLike;
 use PhpParser\Node\Stmt\ClassMethod;
 use PhpParser\Node\Stmt\Function_;
 use PhpParser\Node\Stmt\Interface_;
@@ -30,15 +31,18 @@ final class ReturnedNodesReturnTypeInferer extends AbstractTypeInferer implement
     {
         /** @var Class_|Trait_|Interface_|null $classLike */
         $classLike = $functionLike->getAttribute(AttributeKey::CLASS_NODE);
+        if ($classLike === null) {
+            return new MixedType();
+        }
+
         if ($functionLike instanceof ClassMethod && $classLike instanceof Interface_) {
             return new MixedType();
         }
 
         $localReturnNodes = $this->collectReturns($functionLike);
-
         if ($localReturnNodes === []) {
             // void type
-            if ($functionLike instanceof ClassMethod && ! $functionLike->isAbstract()) {
+            if (! $this->isAbstractMethod($classLike, $functionLike)) {
                 return new VoidType();
             }
 
@@ -92,4 +96,15 @@ final class ReturnedNodesReturnTypeInferer extends AbstractTypeInferer implement
 
         return $returns;
     }
+
+    private function isAbstractMethod(ClassLike $classLike, FunctionLike $functionLike): bool
+    {
+        // abstract class method
+        if ($functionLike instanceof ClassMethod && $functionLike->isAbstract()) {
+            return true;
+        }
+
+        // abstract class
+        return $classLike instanceof Class_ && $classLike->isAbstract();
+    }
 }
diff --git a/rules/type-declaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/parent_override.php.inc b/rules/type-declaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/parent_override.php.inc
new file mode 100644
index 00000000000..4745a87ebd4
--- /dev/null
+++ b/rules/type-declaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/parent_override.php.inc
@@ -0,0 +1,47 @@
+<?php
+
+namespace Rector\TypeDeclaration\Tests\Rector\ClassMethod\ReturnTypeDeclarationRector\Fixture;
+
+use Rector\Core\Exception\NotImplementedYetException;
+
+abstract class ParentOverride
+{
+    public function getValue()
+    {
+        throw new NotImplementedYetException();
+    }
+}
+
+class OverrideParent extends ParentOverride
+{
+    public function getValue()
+    {
+        return 'string';
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\TypeDeclaration\Tests\Rector\ClassMethod\ReturnTypeDeclarationRector\Fixture;
+
+use Rector\Core\Exception\NotImplementedYetException;
+
+abstract class ParentOverride
+{
+    public function getValue()
+    {
+        throw new NotImplementedYetException();
+    }
+}
+
+class OverrideParent extends ParentOverride
+{
+    public function getValue(): string
+    {
+        return 'string';
+    }
+}
+
+?>