Yes, the Sims are generally neglectful. I think if an infant is crying, they will be queued to go to the crib or bassinet. Whether they do what the baby needs will probably depend on their level of parenting skill. But other than that, the player pretty much has to take care of the newborns, infants, and toddlers. I played a variety of the 100 Baby Challenge, where my Sim brought in townie mothers-to-be and sent them home after they gave birth. At one point she had 6 infants in the house and no other adults. But I found that if she invited the mothers over, the infants could click on other adults and get them to take care of most of their needs. But the mothers wouldn't do it on their own.
