the [child/house/mother, etc.] from hell

humorous

the worst or most unpleasant person or thing of that type that anyone can imagine.

His mother's awful. She really is the mother-in-law from hell.

• under the weather
• under the wing of
• under the wing of something
• under the wire
• under thumb
• under wing
• under wraps
• under your belt
• under your breath
• under your nose
• under your own steam
• under your wing
• until are blue in the face
• until hell freezes over
• until kingdom come
• until the cows come home
• until you are blue in the face
• up against
• up against someone
• up against something
• up alley
• up and around
• up and coming
• up-and-coming
• up and running