Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Q: The first year after birth is called infancy. Infancy is a period when the baby grows very fast. During infancy, the baby doubles in length and triples in weight. Other important changes also happen during infancy: The babys teeth start to come in, usually at about six months of age ( Figure 1.1). The baby starts smiling, paying attention to other people, and grabbing toys. The baby begins making babbling sounds. By the end of the first year, the baby is starting to say a few words, such as mama and dada. The baby learns to sit, crawl, and stand. By the end of the first year, the baby may be starting to walk. Childhood begins after the babys first birthday and continues until the teen years. Between one and three years of age, a child is called a toddler. During the toddler stage, growth is still fast, but not as fast as it was during infancy. A toddler learns many new words. The child even starts putting together words in simple sentences. Motor skills also develop quickly during this stage. By age three, most children can run and climb steps. They can hold crayons and scribble with them. They can also feed themselves and use the toilet. From age three until the teens, growth is slower. The body also changes shape. The arms and legs get longer compared to the trunk. Children continue to develop new motor skills. For example, many young children learn how to ride a tricycle and then a bicycle. Most also learn how to play games and sports ( Figure 1.2). By age six, children start losing their baby teeth. Their permanent teeth begin coming in to replace them. They also start school and learn how to read and write. They develop friendships and become less dependent on their parents. There are numerous milestones that occur during the first few years of childhood. These include the use of language, walking and running, understanding simple concepts, pretend play, the development of fine motor skills, the development of independence, Children develop better motor skills as they get older. having temper tantrums, demonstrating separation anxiety, becoming fully potty-trained, showing natural curiosity.
A:
during infancy, a baby