Mary has four daughters, and each of her daughters has a brother. How many children does Mary have?

A word I know, six letters it contains. Subtract just one, and twelve is what remains.

Measure me or scan me then add me up. That will tell you how many there is for you to spare at dinner time. Maybe skip the dessert. Too many of me in there

Eleven siblings have I And I am number ten I should have been the eighth But we got jumbled up again Between the last and first of us They always drop the ball And just before I rest the Weird and wicked come to call What am I?

Almost a square, but not quite right; I have four sides, with two matching twice. All four don’t match, yet corners agree, so what simple shape could I be?