Margaret de La Roche (Reade) - Confusing Daughter is her mother's Mother????

Alice (or Elizabeth) l'Arcedekne, Baroness l'Arcedekne
Gender: Female
Birth: 1287
Roch Castle, Roch, Pembrokeshire, Wales
Death: 1320 (33)
Shepestall, , , England
Immediate Family:
Daughter of Thomas, Baron de la Roche and Margaret de La Roche (Reade)
Wife of Pembrooke Reade; Thomas l' Arcedekne (Arcedekne) and Thomas, Baron l'Arcedekne

Margaret de La Roche MP
Gender: Female
Birth: 1224
Wales
Death: April 1315 (91)
Pembrokeshire, roch Catle, Wales
Immediate Family:
Daughter of Pembrooke Reade and Alice de la Roche, Baroness l'Arcedekne

Alice de la Roche, Baroness l'Arcedekne
Birth: 1287
Roch Castle, Roch, Pembrokeshire, Wales
Managed by: Loryn Clark
Daughter of Thomas, Baron de la Roche and Margaret de La Roche (Reade)
Wife of Pembrooke Reade; Thomas l' Arcedekne (Arcedekne) and Thomas, Baron l'Arcedekne
Mother of Margaret de La Roche (Reade); Alice de Luscote (Archdekne); John, Baron l'Arcedekne and Otes (Eudes) L'Arcedekne
Sister of Lucy le Valence (le Roch); Margaret de la Roche; Joan de la Roche and William de la Roche, Baron Roche
Half sister of Thomas de la Roche and John de la Roche