I only did a time line check on the 12 children, and was able to identify those that would fall within that period for Margaret Warren date of birth to date of death. I found that Joan b. 1425, Cecily b. 1427, Ellen b 1429, Agnes b. 1431, Margery/ Mary b. 1433, George b.1435, and Thomas b. 1437,
Those that did not fall within Margarets death time line is Anne b. 1452, John b.1460, and Humphrey b. 1464.
Listed below is the names and dates of managers that was added the issues to this profile: Joan was added by Scott David Hibbard on 4 Jul 2008, Cecily was added by Scott David Hibbard on 4 Jul 2008, Ellen was added by Scott David Hibbard on 4 Jiul 2008, Agnes was added by Lurent Redfield Ross on 22 Apr 2011, Margery was added by Trevor Rand Scoffield on 15 Feb 2007, Mary was added by (Private) Leitch on 27 Oct 2014, George was added by Tiffany Beesley Brock on 10 Jun 2008, Thomas was added by Joseph Bilodeau on 22 Jun 2007, Anne was added by Susan Bryant (Crammer) on 26 Mar 2007, John was added by Scott David Hibbard on 4 Jul 2008, and Humphrey by Frederick Jame Sieber on 30 Jul 2008. I think this might help. Maybe I'll include the links to their profiles.
Joan Mainwaring
Cecily Mainwaring
Ellen Mainwaring
Margery Egerton Calverley / Hurleton
Mary Mainwaring
George Mainwaring, of Exeter
Thomas Mainwaring
Anne Charleton
John Mainwaring
Hugh Mainwaring, of Nantwich, Gent.
I'm getting tired and confused this profile for now I hope this helps.
Good luck.
Ken
NOTE A: Anne's birth year: "circa 1452". This estimate seems implausible—her parents being about ages 54 and 50.
NOTE B: Is it provable that William Mainwaring (her father) lived to be about age 103?