Hide QML ListView sections dynamically when items filtered

I have a ListView (parent) that uses a ListView (children) as delegate, so each parent is a listView of some items.

To use a typical example, parent list could be a list of sizes (L, M and S), and each child list would be a list of animals of a given size (L animals, M animals, S animals).

Both lists use a custom model that inherits from QAbstractListModel. But the model of children lists used in the view is a custom model that inherits from QSortFilterProxyModel, to have filtering functionalities.

The items of parent list work as "sizes" for children's, so they are used as sections. View is displayed as:

LARGE: – large_animal_1 – large_animal_2

MEDIUM: – medium_animal_1 – …

What I need is that, in case a given section has no items after filtering, section must NOT be shown. With the current view, when there are no "animals" after filtering, section header appears:

LARGE:

MEDIUM: – medium_animal_1 – …

QML code is:

ListView {
        id: headers
        anchors.fill: parent
        clip: true
        boundsBehavior: Flickable.StopAtBounds

        model: _headersModel

        delegate: 
            Item {
                width: parent.width
                height: some_value

                ListView {
                    id: items_of_same_category
                    anchors.fill: parent
                    spacing: 5
                    clip: true
                    interactive: false

                    model: proxy_model

                    delegate: component_delegate
                }
            }

        section.property: "category_value"
                    section.criteria: ViewSection.FullString
                    section.delegate: header_delegate
                    section.labelPositioning: ViewSection.InlineLabels | ViewSection.CurrentLabelAtStart            
    }