“But the icing!” said Sister aloud.  “There’s no icing!  I s’pose Molly didn’t have time.”

If Sister had stopped to think, she would have remembered that all the birthday cakes Molly made—­and she made seven every year for the Morrisons, and one for Grandmother Hastings—­were always iced with pink or white or chocolate icing.

But, you see, she didn’t stop to think, and when she discovered a bowl of lovely creamy white stuff on the small table between the windows, this small girl decided that she would ice the cake and save Molly the trouble.

There was a little film of water over the top of the bowl, but Sister took a wooden spoon and stirred it carefully, and the water mixed nicely with the white stuff, so that she had a bowl filled with the smoothest, whitest “icing” any cook could ask for.

“I’ll get a silver knife to spread it with,” said Sister, who had often watched Molly, and knew what to do.

She brought the knife from the dining-room and had just put one broad streak of white across the top of the cake when Molly came down the back stairs and saw her.

“Sister!” cried Molly.  “What are you doing with my cold starch?”

“I’m icing the cake,” answered Sister calmly.  “You forgot it, I guess.”

Poor Molly grabbed the bowl from Sister’s hands.

“Can’t I leave the kitchen one minute that you don’t get into mischief?” she scolded.  “This isn’t icing—­it’s starch for Mr. Jimmie’s collars.  I’m going to make a beautiful chocolate icing for the cake this afternoon and write Brother’s name on it in white frosting.”

“Oh!” said Sister meekly.

“Go on upstairs, do,” Molly urged her.  “I’ve my hands full today getting ready for the party; can’t you find something nice to do upstairs?”

Thus sped on her way, Sister reluctantly mounted the stairs to the second floor.

“I could play jacks with Nellie Yarrow,” she said to herself.  “Only she’s lost her jackstones and I can’t find mine.  What’s that on Dick’s bureau?”

Ralph and Jimmie roomed together, but Dick had a room of his own, and though Sister was strictly forbidden to meddle with his things, they had a great attraction for her.  She could just see the top of Dick’s chiffonier from the floor and now she dragged a chair up to it and climbed up to see what the shining thing was that had caught her eye.

It was a gold collar button, and Dick, she found, had a box of pearl and gold buttons that Sister was sure she had never seen before.  She played with them, tossing them up and down and watching them glitter, until a sudden thought struck her.

“They’d make lovely jackstones,” she whispered.  “I could use ’em and put them right back.  I know Nellie has a ball.”

Dick had several new ties, and Sister had to admire these before she could leave the chiffonier.  Finally she slipped the box of pretty buttons in her pocket and jumped down.  She put the chair where she had found it, and ran downstairs and through the hedge that separated the Morrison house from that of Dr. Yarrow’s.