APRON comes untied
1818 Edinburgh Mag. Nov. 410 [Angus: mishap at wedding of girl obstinate enough to marry in May] In walking to church, her apron-strings loosed, and it fell in the path before her.

1861 C. C. ROBINSON Dialect of Leeds 300. For a married woman's apron to fall off is a sign that something is coming to vex her; but when the apron of an unmarried female falls off, there is nothing surer than that she is thinking about her sweetheart.

1872 H. CULLWICK Diary 14 Sept. My apron string got loose as I stood in the station yard … So I thought, ...