Display Date Difference in Years Months Days

Using Local javascript Code External version embeded as inc/date2date.js on my website. Comments on the code source page identify problems but no solution provided.

The output from TryDate2Date.html (this file on website) is Exactly what I am looking for
but there is an error in the code.

When the display should say
XX years 11 months and 18 days it displays only
XX years and 18 days – any other difference is displayed correctly as far as I know.

Also See:   TryDate2DateFailTest.html