Physical development includes physical growth and the development of body systems such as the digestive system and the immune system. It also includes the development of fine and gross skills which is the movement of major and fine muscles found in our arms, legs, fingers, and toes.Physical development begins before birth and continues throughout childhood and adolescence, and rounds off in adulthood. Children naturally develop gross motor skills before fine motor skills.Gross motor skills develop as children learn to use their large muscles. Learning to sit up, pick up an object, stand and eventually walk are examples of gross motor skill development in children from birth to age one. Coordination of the large muscles is crucial for these activities in the first year of life and those that will go after as the child grows. Fine motor skills flourish when children learn to use their small muscles. Learning to pick up small objects using the pincer grip, holding toys, and shaking toys are examples of some fine motor skills children learn in their first year of life. Fine and gross motor skills rely on muscles, nerves, and the brain to coordinate movement. There are many areas in the brain that are responsible for the development of motor skills. In sync those areas aid to control everything from eye-hand coordination to things like walking and running. If your three-month-old fails to practice lifting his or her head alone, then the neck muscles do not get the opportunity to strengthen. This could cause the baby to have later delays in the development of other gross motor skills, such as torso control. When infants are given are given tummy time, an opportunity to lie on their stomach, the caregiver is giving the baby the opportunity to strengthen their neck and back muscles and laying the groundwork for the development of other gross motor skills. It is important that caregivers provide many opportunities and activities for their children to build and strengthen both gross and fine motor skills.