Newborn giant pandas are exceptionally small at birth, weighing 90-130g, one-nine hundredth of their mother's weight. Indeed, the giant panda holds the record among placental mammals for having the largest mother: newborn weight ratio. They are blind and toothless and pink and naked except for a sparse covering of white hair. But for all its fragility, indeed because of it, a newborn panda has a very loud voice totally out of proportion to its tiny body. Having a mother big enough to crush you with an accidental swish of her paw or a languid stretch of her body makes it essential to let her know quite unambiguously that you are feeling discomfort. Natural selection has long since weeded out the feeble criers. An infant's repertoire is limited to one call only, a loud squawk, which is simple but very effective and is all a baby panda needs. Panda cubs lack the high-pitched grunts and loud, harsh purrs (keckering) of nursing ringtails (a species of racoon) and bears, calls which are thought to stimulate their mother to release milk and to take up a suitable nursing posture.

An infant giant panda is often nowhere to be seen, tucked beneath the mother's chin or hidden under a large hairy forepaw as she reclines. Sometimes the only sign of a cub is a long pink tail, proportionately much longer than an adult's, sticking out from under the female's paw. The baby suckles frequently in the first few days of life, about six to a dozen times a day for up to thirty minutes each time. The mother seems aware that any rough handling on her part could spell the end of a young life and so she compensates by being especially gentle, holding the baby in her jaws across its shoulders or back, or clasped against her body with her forepaws.

The den is a vital refuge for the mother and her young from birth to about one month. A female does not travel much in the early days of baby care but is very restless and shifts her position time and time again. The female may remain within her den for a whole month, venturing out to forage and drink for short periods only. But she becomes very restless, there will be a sharp increase in the number of times she changed from one activity to another. During this fidgety period, the female is not very interested in food and does not defaecate or urinate very often. In fact, she is more concerned with making sure that the baby does all these things that she does not. Between bouts of suckling and vigorous grooming, she encourages the cub to urinate and defaecate by licking its anus and eats the baby's wastes. When finished nursing she also licks the infant clean. This licking is very important since it keep the infant clean and warm, and helps the infant’s immunity and increases the infant’s skin microcirculation and prevents excess moisture evaporation.

Mother pandas keep their dens clean, either leaning out of the den entrance to defaecate or moving further afield. Such attention to hygiene reduces the risk of infections in the cubs. In addition to an outside toilet, a handy source of drinking water is another important amenity for a lactating female confined to the nursery. In Wolong, all three breeding dens in use were positioned near rivulets.

By the end of the first week, the black of the eye patches, ears and shoulders is just visible, and by the middle of the following week, the black has extended into the adult pattern. The hair is denser, too. The infant looks like a miniature adult by the third week of life, apart from its tail which is still long. The eyes are open fully around week seven and the infant can raise its head and crawl by this time, but its coordination is still poor. The end of the second month sees the baby suckling about half as frequently as it did at birth and this declines further with age. The first teeth, either canines or incisors, appear towards the end of the third month. The infant can now walk, albeit clumsily. At 5 months of age, the young panda is well in control of its movements, walking, trotting, rolling around playfully and climbing onto its mother's back.

At 6 months of age, the cub has a set of 26 to 28 teeth (all except the molars) which it puts to good use in starting to eat young bamboo leaves. Some two to three months later, around spring of the following year, young pandas become adept at consuming and digesting bamboo shoots. Now fully weaned and nutritionally independent of their mothers, they are still not yet ready to leave the nest and establish home ranges of their own. For one thing, they are still vulnerable to large predators, and for another, they need more experience in social communication and interaction. So they remain with their mother all through the breeding season, during which her normal mating urges are suppressed, and throughout summer and autumn. The young pandas, now hulking 1 and a half -year-old sub-adults of almost adult weight, leave their mothers just before winter begins in earnest.