[eru]

I am saying that people choose a target number of offspring that make it to adulthood. If more kids die in infancy, they'll have more babies to make up the difference.

If less kids die in infancy, they will have less babies to make up the (negative) difference.

By the way, please have a look at http://economics.ucdavis.edu/events/papers/WuLeminJMPMalthus... and tell me what you think.