The little scatterbrain had, of course, forgotten her cloak.

But, monstrous! There was Catherine stripping off her own, Rose refusing it.

In vain.

The sister's determined arms put it round her.

Rose is enwrapped, buttoned up before she knows where she is, and Catherine falls back, pursued by same shaft from Rose, more sarcastic than grateful to judge by the tone of it.
'Miss Leyburn, what have you been doing ?' 'Rose had forgotten her cloak,' she said, briefly; 'she has a very thin dress on, and she is the only one of us that takes cold easily.' 'You must take my mackintosh,' he said at once.
She laughed in his face.
'As if I should do anything of the sort!' 'You must,' he said, quietly stripping it off.