By Alison Smith-squire For The Daily Mail With his smiling mother and aunt, this is little Fionan Terry in one of the first portraits of his extraordinary family. But the happy picture belies the emotional roller-coaster the two sisters have endured to bring him into the world. For not only is Ellie Fairfax his aunt, she is also his surrogate mother – stepping in to carry the baby after her sister learnt treatment for cervical cancer would leave her infertile. Scroll down for video Happy family: Siobhan Terry, left, and surrogate mother and sister Ellie Fairfax with three-month-old Fionan Adorable: He is biologically Ellie's son but she says she only ever thought of him as Siobhan's baby
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Siobhan Terry, 31, was left infertile after cervical cancer treatment
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Her sister Ellie Fairfax, 33, stepped in to give birth to little Fionan
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Ellie moved in with Siobhan, husband Dean and Fionan for first week
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He is biologically Ellie's baby but she 'only ever thought of him as Siobhan's'
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Mrs @placeholder said: ‘Words cannot express how much I can ever thank Ellie for what she’s done.