如果将个别孩子从父母身上移除，如何检查剩余人数

Every thing is working fine let say if I check and uncheck any parent so it will save/remove corresponding records from role_menu table you can see the jstree structure and tables in attachment. If I remove individual child from its parent then if last one is remaining then parent should also removed from role_menu. How to check or count last child.

Role_Menu

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JSTREE

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Menus

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