Agatha (dsp shortly before 27 Dec 1261), daughter and heir of Roger de Clere of Brumlegh, Surrey and Ludborough, Lincoln. [Magna Charta Sureties]
Note: I am not sure how to read the above. MCS cannot mean that Agatha "dsp" because in the same statement she is said to have a daughter (Alice) by her husband William le Rus.