Upstairs Berta was helping with the beds — not very successfully because she was not used to doing things for herself. But she was very willing to learn and Aunt Fanny was quite pleased with her. Timmy and Sally darted about together and made things rather more difficult than they need have been, popping under beds and out again at top speed.

“I’m glad Timmy likes Sally,” said Berta. “I knew he would. I can’t think why George thought he wouldn’t. George is funny, I think.”

“Not really,” said Aunt Fanny. “She hasn’t any brothers or sisters to rub off her corners, and she didn’t even know her three cousins till a few years ago, or go to school. Lonely people aren’t so easy to get on with as others — but she is great fun now, as you will soon find out.”

“I’m an only child too,” said Berta. “But I’ve always had plenty of other children to play with. My Pops saw to that. He’s wunnerful — I mean wonDERful. I’ll say that word “wonDERful” twenny times, then maybe I’ll get it right.”

“Well, say the word “twenty” as well!” said Aunt Fanny. “It has a letter T at the end as well as at the beginning you know. It’s “twenTY” not “twenny.” But don’t make yourself too English. It’s nice to have a change!”

“WonDERful, wonDERful, wonDERful! TwenTY, twenTY!” chanted Berta, as she made the beds. Dick looked into the room and chuckled.

“Great snakes!” he said, with a grin, and an American accent. “You shore are wunnerful, baby!”

“Don’t be so silly, Dick,” said his aunt, laughing. “Now — I think we’ve finished all we have to do, Berta. We’ll go downstairs and have a conference. Tell the others, will you.”

Berta, followed closely by Sally, who was also followed closely by an adoring Timmy, went to tell Dick and Julian, and then George and Anne. George was not too pleased with Timmy.

“Where have you been?” she said. “Can’t you stop running about after Sally? She’ll get very very tired of you!”

“Wuff!” said Sally, in a high little bark, not at all like Timmy’s deep “Woof!”

Soon all five children and two dogs, and also Joan, were in the sitting-room with Aunt Fanny. Berta began to look a little nervous.

Aunt Fanny had the letter that Berta’s father had sent. She did not read it out to the children, but told them what was in it. She also explained to Joan about Berta.

“Joan, you have always known what important work the master does,” she said. “Well, Miss Berta’s father does the same kind of work in America, and he and the master are working on a great new scheme together.”

“Oh yes, Mam,” said Joan, very much interested.

“Berta’s father has been warned by the police that it is possible Berta may be kidnapped and held to ransom, not for money, but for the scientific secrets that he knows,” went on Aunt Fanny. “So she has been sent to us to be kept safe for three weeks. By that time the scheme will be finished and made public. Berta is going to the same school as Miss Anne and Miss George, and it is a good idea to let them know one another first.”