If you want to include a date value in a cell using CONCATENATE to combine text and other cells, you need to include the TEXT function and include the format of the date you want.
|A||B||C||< C function >|
|1||Stephen||18/12/1946||Stephen’s birthday is 18/12/1946||=CONCATENATE(A1,”‘s birthday is “,TEXT,(B1,”dd/mm/yyyy”))|
|1||George||14 May 1944||George’s birthday is 14-May-1944||=CONCATENATE(A2,”‘s birthday is “,TEXT,(B2,”dd-mmm-yyyy”))|
|1||Christopher||30-7-70||Christopher’s birthday is 30 December 1970||=CONCATENATE(A3,”‘s birthday is “,TEXT,(B3,”dd mmmm yyyy”))|