diff --git a/share/man/man9/sysctl.9 b/share/man/man9/sysctl.9
--- a/share/man/man9/sysctl.9
+++ b/share/man/man9/sysctl.9
@@ -23,7 +23,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd September 1, 2020
+.Dd September 9, 2025
 .Dt SYSCTL 9
 .Os
 .Sh NAME
@@ -97,7 +97,6 @@
 .Nm SYSCTL_UQUAD
 .Nd Dynamic and static sysctl MIB creation functions
 .Sh SYNOPSIS
-.In sys/param.h
 .In sys/sysctl.h
 .Fn SYSCTL_DECL name
 .Ft struct sysctl_oid *
diff --git a/sys/sys/sysctl.h b/sys/sys/sysctl.h
--- a/sys/sys/sysctl.h
+++ b/sys/sys/sysctl.h
@@ -41,6 +41,13 @@
 #include <sys/tree.h>
 #endif
 
+#include <sys/cdefs.h>
+#include <sys/_types.h>
+#ifndef _SIZE_T_DECLARED
+typedef	__size_t	size_t;
+#define	_SIZE_T_DECLARED
+#endif
+
 /*
  * Definitions for sysctl call.  The sysctl call uses a hierarchical name
  * for objects that can be examined or modified.  The name is expressed as
@@ -1223,13 +1230,6 @@
 struct sbuf *sbuf_new_for_sysctl(struct sbuf *, char *, int,
 	    struct sysctl_req *);
 #else	/* !_KERNEL */
-#include <sys/cdefs.h>
-#include <sys/_types.h>
-#ifndef _SIZE_T_DECLARED
-typedef	__size_t	size_t;
-#define	_SIZE_T_DECLARED
-#endif
-
 __BEGIN_DECLS
 int	sysctl(const int *, unsigned int, void *, size_t *, const void *, size_t);
 int	sysctlbyname(const char *, void *, size_t *, const void *, size_t);