My brother is trying to become a guardian of his child at the moment. She is being cute using her family law knowledge to stop him getting guardianship I think. If she lives with him for 12 months, 3 of which have to be after the baby's birth he gets automatic guardianship. That's why she is back and forth (or back with) the mother.
"Automatic guardianship
If a child is born outside of marriage, the mother is the automatic guardian. The position of the unmarried father of the child is not as certain. An unmarried father will automatically be a guardian if he has lived with the child's mother for 12 consecutive months after 18 January 2016, including at least 3 months with the mother and child following the child's birth. If there is disagreement as to whether they have been cohabiting for the required length of time, an application for the necessary declaration can be made to the court."
Source:
Law regarding guardianship of children of non-marital relationships.
www.citizensinformation.ie
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