is there a way to set a parbox to a minimum height?

i'm looking for a way to make it so that my \parboxes keep a minimum height, similar to CSS min-height , e.g.

\mhparbox{\textwidth}{3cm}{...}

would ensure that whatever text appears in place of ..., the resulting box will at least take up 3cm of vertical space. does a package to that effect exist or is there maybe a solution using \savebox?