Among the closely watched demographic trends of the late 20th Century is a pronounced drop in fertility rates throughout much of the world. Italy presents a particularly interesting case for study: in 1960, Italy’s total fertility rate (TFR) was 2.41; by 1995 it had fallen to 1.17. According to United Nations projections, by 2050 Italy will be the second oldest country in the world, with 3.4 persons aged 60 or older for each person under age 15. Besides overall population aging, another implication of sustained low fertility is smaller families and kin groups. We investigate the consequences of projected changes in Italy’s birth and death rates on the composition of kin groups using microsimulation techniques. Using a starting population taken from the 1994 “Indagine Multiscopo sulle Famiglie” survey and projected rates of mortality and fertility by age and parity produced by the Italian Institute of Statistics, we simulate the path of kin-group patterns in Italy during the period 1994-2050. While we reproduce the aggregate population patterns found in official projections, we conduct our estimates at the “micro” level, keeping track of the relationships between individuals, which underlie kin group patterns. We show the effects of the demographic trends on the existence of daughters and sons for older mothers, on the number of sisters and brothers with whom an adult woman could share the responsibilities of caring for an elderly mother, and the effect of the joint action of the increase in longevity and the mean age at fertility on the proportion of adult women with a living mother