i do a variation of dar and som.

i give each kid a four-letter last name, made from the first syllable of the mother and the first syllable of the guy.

and each man and each woman has a child, to keep it even.

oh, and ella: you can name kids in the detail screen. click on the name and then type when the cursor blinks. and if you've opened the school, you can get a clue to whose kid is whose by comparing the skills level of each kid to the skills level of each mom.