Under their Children, press What are you trying to fix? and choose the option saying a child isn't theirs. Then say whose child they really are, or keep a space with an empty card until you know. The child stays on the tree – only the link changes. For example, if your cousin Amy shows as your dad's daughter but she's really his brother Mike's, move her to Mike.
Where to find it
Person page (Safe edit on) → under Parents, Partners or Children → What are you trying to fix?
Only people with the "Add people" and "Remove" ticks, with Safe edit on.
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