Use of "ill afford"

Hi

Does the phrase "ill afford" (roughly) mean the same as "not afford"? Are these sentences natural?

She could ill afford another loss in the new business.

Why should you buy a car/house you can ill afford?

(Doctor to a person whose father had a fall)

Take care of your father. He can ill afford another fall.

The water level in the river is dangerously high. We can ill afford more rains.

Thanks,

Tom