Quote 1, from the series The Mysterious Benedict Society:

" I'm coming, too!" Kate said, hurrying after him.

"We'll all come," said Reynie.

Milligan around and held his hand in warning.  "No, you won't. These stairs may be unsound. You stay here, and I'll be back in a minute. I mean it, now. Stay out." Composing his face into a serous expression, he went up the stairs and disappeared through the door at the top.

The children waited until the door had closed and Milligan was out of earshot. Then they went up after him.

-Page 252, The Perilous Journey

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