Dear Sharon and Dale,
I have copy of "The roll of the house of Lacy" written Edward de Lacy-Bellingari in 1928 and updated by Bernhard Larscy.
In this book (almost 700 pages) is written about John de Lacy, Constable of Chester, Baron of Halton, Lord of Pontefract, etc. He married Lady Alice de Vere, sister of William Mandeville, third Earl of Essex (ob.1189)
His issue of her were: Roger, Eustace, Richard, Peter and Alice.
Other issue were: Albert de Lacy (expelled from England and Normandy for overmuch comment on the murder of the King's nephew, Prince Arthur), Margaret (a nun), Richard (killed in Wales), Robert of Flamborough Castle and Lordship, John de Crusader (m.Alice Mandeville,ob. in Cyprus island) and Agnes (m. Lord Monhalt). Of Alice Mandeville John had a son, Geoffrey, heir to the third part of the Earldom of Essex, who, according to the Harleian manuscripts, died in the King's custody, but left issue. In the latter list there is evident confusion anent both (?) Johns de Lacy.
Kind regards
Jan Gutkowski
John de Lacy, Lord of Halton, Constable of Chester is my 6th cousin 21 times removed.