You may want to set the default subhead height, to control whether the subhead gets automatically added when using the Head and  Body tool.

The default value is 0pt, which means the subhead is not added.

On the Split subtab of the Extra tab on the Preferences dialog box, in Subhead Size, enter a suitable single value, e.g. 22pt.

Notes

•This functionality uses the variable AFCS_SubheadSize.