The Fundationis et Fundatorum Historia of Forde Abbey names (in order) "Johannem…Hugonem tertium…Robertum…ac Thomam" as the sons of "dominus Hugo secundus" & his wife.
The Fundationis et Fundatorum Historia of Forde Abbey records that Thomas, son of "dominus Hugo secundus", married "Murielæ senioris filiæ et hæredis domini Johannis de Mules". 1
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On 6 October 1337, Thomas de Courtenay having done fealty, he and Muriel received their pourparty of her father's lands, and on 3 March 1337/8 their pourparty of knights' fees.
Thomas and Muriel had one son, Hugh, who died s.p. and two daughters, (a) Muriel, who m. Sir John de Dinham..., and (b) Margaret, who margaret Sir Thomas Peverel.... 2