diff --git a/include/kvpp/kvpp.h b/include/kvpp/kvpp.h
index 4639238dd..33d258a6f 100644
--- a/include/kvpp/kvpp.h
+++ b/include/kvpp/kvpp.h
@@ -53,7 +53,7 @@ class KV1Element {
 	[[nodiscard]] const std::vector<KV1Element>& getChildren() const;
 
 	/// Get the child element of the element at the given index
-	[[nodiscard]] const KV1Element& operator[](std::size_t index) const;
+	[[nodiscard]] const KV1Element& operator[](unsigned int n) const;
 
 	/// Get the first child element of the element with the given key
 	[[nodiscard]] const KV1Element& operator[](std::string_view childKey) const;
diff --git a/src/kvpp/kvpp.cpp b/src/kvpp/kvpp.cpp
index 8c0657810..3195080c2 100644
--- a/src/kvpp/kvpp.cpp
+++ b/src/kvpp/kvpp.cpp
@@ -41,8 +41,8 @@ const std::vector<KV1Element>& KV1Element::getChildren() const {
 	return this->children;
 }
 
-const KV1Element& KV1Element::operator[](std::size_t index) const {
-	return this->children.at(index);
+const KV1Element& KV1Element::operator[](unsigned int n) const {
+	return this->children.at(n);
 }
 
 const KV1Element& KV1Element::operator[](std::string_view childKey) const {