menu not linked child pages should be marked in the menu

Hi!
I have the following problem: I have a parent page that’s linked in the menu, and everything is displayed correctly. The child pages aren’t linked in the menu, but should still be highlighted in the respective menu item. (In my case, the menu item should be underlined.)

For example:
menu: Home – Food – Drinks – Contact
Page drinks is parent, page wine is child and not linked from the menu but Drinks should be marked as active

How can this be resolved?
Thank you!