Ruth Blakely, in her book on the Bruses, suggests that Joan’s maritagium of land and a mill at Knottingley in the Lacy honour of Pontefract indicates some stroung relationship with that Lacy family.

TFPL, Aug 2006: In Coll Top et Gen, it says that he was buried at Guisborough Priory with ‘Joan doughter of the Erle of Chester’.  Very interesting and I wonder which earl?  Hugh de Kivelioc looks likely from the dates, though his known daughters were heiresses and well documented, so she might be one of his bastards, hence the not so grand marriage with Peter de Brus?
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Rosie Bevan in her article “Keeping it in The Family” in Foundations pub by FMG as Vol 5 in May 2013 states that Joan was very likely the daughter of John the Constable of Chester, giving several pages of associated evidence.

I have accepted this proposal as reasonable and thereby show Joan as the daughter of John the Constable and Alice de Vere.
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