Same-sex marriage goes against the natural order

The word ‘marriage’ is derived from the Latin ‘matrimonium’, meaning ‘mother’ and ‘motherhood’, which imply fatherhood and children. 

If that is what marriage is about, can a same-sex couple ask for marriage to be accorded to them? They cannot give what their parents gave to them: ie a father and a mother. Is it not impertinent to claim a status the conditions of which one cannot meet?

If the call to acknowledge and respect the obvious qualifications for marriage will not be heard, have we not reached a stage where debate is no longer possible?