ACCESS 07 age calculation display

I have Access 07 table with DOB field. I created a query with 1 field that calculates a persons age in years and 2nd field that shows age in months.
Code in the query fields are:

Year: DateDiff(“yyyy”,[DOB],Now()) Int(Format(Now(),”mmdd”)Format([DOB],”m”))

Id like to have a single field that shows any age under 1 year as months then anything over 12 mths would show up in years.
I have no clue how tho get the results
Thanks