Green’s Dictionary of Slang

1. water.

1946		St. Vincent Troubridge ‘Some Notes on Rhyming Argot’ in AS XXI:1 Feb. 46: mother and daughter. Water. (Origin doubtful, probably English.) This again, if English, is rare. I have never heard anything except ratcatcher’s daughter (from a popular song of the 1850’s), or didn’t ought ter.
1960, 1975		Wentworth & Flexner DAS.
2002		B. Kirkpatrick Wicked Cockney Rhy. Sl.

2. a daughter.

1977

D. Powis Signs of Crime 180: Didn’t oughter Daughter.