“Sole responsibility” is a factual matter to be decided upon all the evidence. Where one parent is not involved in the child’s upbringing because he (or she) had abandoned or abdicated responsibility, the issue may arise between the remaining parent and others who have day-to-day care of the child abroad. The test is whether the parent has continuing control and direction over the child’s upbringing, including making all the important decisions in the child’s life. However, where both parents are involved in a child’s upbringing, it will be exceptional that one of them will have “sole responsibility”.