*Juliana FitzGerald
born about 1243 Ireland
died after 1309

father:
*Gerald Fitzmaurice
born about 1215 Adare, Limerick, Ireland
died 1243 Gascony, France

mother:
unknown

siblings:
Maurice FitzMaurice Fitzgerald born about 1241 Ireland

spouse:
*Thomas de Clare
born about 1248 Tonbridge, Kent, England
died February 1287/88 Thomond, Connaught, County Clare, Ireland
married Essex, England

children:
*Maud de Clare born about 1276 Gloucestershire, England died 1 February 1327
Richard de Clare born about 1278 Essex, England died 7 June 1318 Dysert, Ireland
Gilbert de Clare born about 1281 christened 3 February 1281 Munster, Limerick, Ireland
died before 16 November 1307
*Margaret de Clare born about 1280/86 Chilham Castle, Kent, England or Thomond, Connaught, County Clare, Ireland
died 1333 Castle Badlesmere, Kent, England

biographical and/or anecdotal:

notes or source:
LDS
ancestry.com
Of 648 entries 647 list Juliana (Julian) as the daughter of her brother and his wife Emmeline Longespee both of whom were incontrovertibly born in 1250. One entry names her Juliana FitzGerald with no father.
Gerald was Maurice's father and therefore may be Juliana's father.
In any event all are descended from *Maurice Fitzgerald and *Juliana Cogan so there is only a momentary (one generation) error if this is not the case.