diff --git a/Userland/Libraries/LibCore/System.cpp b/Userland/Libraries/LibCore/System.cpp
index 46766b0c90..d360c4d4f5 100644
--- a/Userland/Libraries/LibCore/System.cpp
+++ b/Userland/Libraries/LibCore/System.cpp
@@ -20,6 +20,10 @@
 #include <termios.h>
 #include <unistd.h>
 
+#ifdef __serenity__
+#    include <serenity.h>
+#endif
+
 #define HANDLE_SYSCALL_RETURN_VALUE(syscall_name, rc, success_value) \
     if ((rc) < 0) {                                                  \
         return Error::from_syscall(syscall_name, rc);                \
@@ -125,6 +129,12 @@ ErrorOr<long> ptrace(int request, pid_t tid, void* address, void* data)
         return Error::from_syscall("ptrace"sv, -errno);
     return rc;
 }
+
+ErrorOr<void> disown(pid_t pid)
+{
+    int rc = ::disown(pid);
+    HANDLE_SYSCALL_RETURN_VALUE("disown", rc, {});
+}
 #endif
 
 #ifndef AK_OS_BSD_GENERIC
diff --git a/Userland/Libraries/LibCore/System.h b/Userland/Libraries/LibCore/System.h
index c13a938d55..60ffea982b 100644
--- a/Userland/Libraries/LibCore/System.h
+++ b/Userland/Libraries/LibCore/System.h
@@ -41,6 +41,7 @@ ErrorOr<void> ptrace_peekbuf(pid_t tid, void const* tracee_addr, Bytes destinati
 ErrorOr<void> setgroups(Span<gid_t const>);
 ErrorOr<void> mount(int source_fd, StringView target, StringView fs_type, int flags);
 ErrorOr<long> ptrace(int request, pid_t tid, void* address, void* data);
+ErrorOr<void> disown(pid_t pid);
 #endif
 
 #ifndef AK_OS_BSD_GENERIC