Sir John Warren, Kt. - Missing Generation

Obviously this information is wrong due to the birthdates of the father and son.
Here is the correct information according to Earwaker:

◦2. Sir John de Warren of Poynton and Stockport, knight, born about 1343, died 1387 and buried at Boton in Norfolk. Inquisition post mortem in 1392.
◦+ Margaret, daughter and heiress of Sir John de Stafford of Wickham, Norfolk, knight. Marriage settlement dated 1371. (She remarried John Mainwaring of Over Peover about 1387 and died 1418. There is a monument to her at Over Peover.) Sir John de Warren had a son Nicholas and a daughter, Margaret.

source:
http://www.thornber.net/cheshire/htmlfiles/warren.html