IDIOMS

apron string

(idiomatic, usually pluralized) A symbol of the domestic ties binding a male to a female (as a husband to a wife or a son to a mother).

Example: One of the pair of strings or narrow sewn clothstrips used to fasten an apron around the wearer's waist.
1852, William Makepeace Thackeray, The History of Henry Esmond, Esq., ch. 7:
  [T]he opinion of the country was that my lord was tied to his wife's apron-strings, and that she ruled over him.
1914, Thornton W. Burgess, The Adventures of Jerry Muskrat, ch. 1:
  "Pooh!" said Jerry, throwing out his chest, "I guess I can take care of myself without being tied to my mother's apron strings!"