Hi David, Two possibilities come to mind: 1. The ages may not be transcribed correctly in the first place - you would need to check the original enumerator's page and perhaps other censuses to confirm that the ages given are consistent 2. Mother-in-law may be stepmother (having married a widowed husband much older than herself with grown-up children). I have in my own family tree a mother and daughter - both widowed - who married brothers two years apart in age, so I can believe almost anything is possible where convoluted relationships are concerned! Best wishes, Roz