Kie, in situations like the one you describe, I typically add a numbered list of probable children (and who they married) into the biography section of the parents' profiles. That does not actually affect the shape of the Wikitree, but it often leads to conflict resolution. You might discover that some of the children are actually the same person with slightly different names and should be merged. Or, that one or more of the children linked to the family are mis-attributed, based on geographic considerations. For example, I've seen mis-attributed children said to have been born a location different from their older and younger siblings. This is not an impossible scenario, but it is highly unlikely. Sometimes, children are said to be not-the-same based on them having married different spouses--when actually, they married twice and each profile has one of the spouses attached. Overall, listing children in this way tends to lead to resolution.