An hour later, he came down-stairs again.  “Is she sleeping?” he asked of Fairy in a low voice.  “That is good.  You have your work cut out for you, my girl.  The little one here will be all right, but this twin is in nearly as bad shape as the one up-stairs.”

“Oh!  Doctor!  Larkie, too!”

“Oh, she is not sick.  But she is too intense.  She is taking this too hard.  Her system is not well enough developed to stand such a strain very long.  Something would give way,—­maybe her brain.  She must be watched.  She must eat and sleep.  There is school to-morrow, isn’t there?”

“But I am sure Lark will not go, Doctor.  She has never been to school a day in her life without Carol.  I am sure she will not go!”

“Let her stay at home, then.  Don’t get her excited.  But make her work.  Keep her doing little tasks about the house, and send her on errands.  Talk to her a good deal.  Prudence will have her hands full with the other twin, and you’ll have all you can do with this one.  I’m depending on you, my girl.  You mustn’t fail me.”

That was the beginning of an anxious week.  For two days Carol was in delirium most of the time, calling out, crying, screaming affrightedly.  And Lark crouched at the foot of the stairs, hands clenched passionately, her slender form tense and motionless.

It was four in the afternoon, as the doctor was coming down from the sick room, that Fairy called him into the dining-room with a suggestive glance.

“She won’t eat,” she said.  “I have done everything possible, and I had the nurse try.  But she will not eat a bite.  I—­I’m sorry, Doctor, but I can’t make her.”

“What has she been doing?”

“She’s been at the foot of the stairs all day.  She won’t do a thing I tell her.  She won’t mind the nurse.  Father told her to keep away, too, but she does not pay any attention.  When I speak to her, she does not answer.  When she hears you coming down, she runs away and hides, but she goes right back again.”

“Can your father make her eat?  If he commands her?”

“I do not know.  I doubt it.  But we can try.  Here’s some hot soup,—­I’ll call father.”

So Lark was brought into the dining-room, and her father came down the stairs.  The doctor whispered an explanation to him in the hall.

“Lark,” said her father, gently but very firmly, “you must eat, or you will be sick, too.  We need all of our time to look after Carol to-day.  Do you want to keep us away from her to attend to you?”

“No, father, of course not.  I wish you would all go right straight back to Carrie this minute and leave me alone.  I’m all right.  But I can’t eat until Carol is well.”

Her father drew a chair to the table and said, “Sit down and eat that soup at once, Larkie.”

Lark’s face quivered, but she turned away.  “I can’t, father.  You don’t understand.  I can’t eat,—­I really can’t.  Carrie’s my twin, and—­oh, father, don’t you see how it is?”