His parents seem the same as his wife's parents
The parents for Thomas Fitzgospatric are
Gospatrick 1105-1179 Gospatrick of High Ireby, Lord of Workington
Egelina 1114-1133 Lady Egelina de Workington
The parents for his wife, Grace Ireby are
Gilbert or Gospatrick 1105-1179 Gilbert or Gospatrick Ireby
Egeline 1108-1133 Egeline (D'Engaine Ireby) Engaine
I'm thinking his parents are Gospatrick and Egelina d'Engaine. The parents of his wife (who was Grace de Culwen -NOT his sister Grace Irby) would be Thomas de Culwen and unknown dau of Fergus.
see http://www.washington.ancestryregister.com/GALLOWAY00006.htm#i5032
What do you think?