More than one-third of the 2,490 identified so far buried at Bethel Burying Ground are infants 2 years old and younger. The lack of a nutritional diet accounts for the majority of these deaths. Starvation was a very real problem for the desperately poor families. More often it was a lack of protein (meat) that was expensive and out of reach of many families. Also, the inability of pregnant women to obtain adequate nutrition contributed to the birth of babies with weakened immune systems that made them more susceptible to a long list of deadly diseases.
For an excellent overview of the subject see African Americans in Pennsylvania: Shifting Historical Perspectives, pages 335, 337, 343-44, 353, 354-55.