Alpacas welcome their young, called crias, after a pregnancy lasting roughly 11 months. This gestation period, ranging from 335 to 345 days, typically results in a single, healthy cria although on few very rare occasions there can be twins. Unusually alpacas generally birth during the day.
Newborn crias are surprisingly precocious. Within minutes or an hour of birth, they stand on their wobbly legs and find their way to mom for their first taste of nutrient-rich alpaca milk. These fuzzy bundles of joy weigh in at a birth weight of 7 to 10 kilograms. The first 24 hours are critical and it takes a great deal of attention from their owners to ensure they get the vital colostrum to ensure they get all the antibodies they need to build a healthy immune system. Healthy cria are quickly active and will run around their field and play with their friends pronking in the sunshine on a summers day. 
As the cria grows, it becomes increasingly independent. While nursing remains crucial, crias begin nibbling on hay and pasture as early as a few weeks old. Their rumens, the first chamber of their complex, multi-chambered stomachs, develop gradually. This is why weaning shouldn't happen before 3.5 months of age, even though crias often show interest in solid food much earlier. Ideally, weaning occurs around 5 to 6 months old, when the cria weighs around  35 to 40 kilograms and its rumen is fully functional. The separation or weaning process needs to be carefully managed to ensure minimal stress for both cria and mother.