The phrase "flies the coop" refers to someone leaving a place suddenly and without permission. The antonyms for this phrase are staying put, remaining in place, and settling down. When a person decides to stay put, they are choosing to remain where they are instead of leaving. When they remain in place, they are not moving away from their current location. Finally, when someone settles down, they are choosing to establish themselves in a place, rather than leaving it. These antonyms are useful for when one wants to convey the opposite of "flies the coop" and communicate the idea of staying put or settling in.