V1 angles posteriorly between longus colli medially and scalenus anterior laterally behind the common carotid artery to enter the transverse foramen of C6. Relations: 1  anteriorly: common carotid artery, vertebral vein, thoracic duct (left VA) and lymphatic duct (right VA).
9. For an easy-to-use graphical illustration of when baby should sit up, please see our baby development chart. What this information says is that at age 7 months, roughly 70% of all babies can sit alone for short periods of up to about half a minute. And 90% of all babies can do so by about 9 months old..Similarly, by about 3 months about 50% of all babies can sit when supported with cushions. Letâs say have a baby of about 7 months old who does not sit alone for short periods.nd 90% of all babies can do so by about 9 months old.. Similarly, by about 3 months about 50% of all babies can sit when supported with cushions. Letâs say have a baby of about 7 months old who does not sit alone for short periods.
At about age 6 months, infants can usually oppose the thumb in the grasping motion. Most infants can sit without support also around this age. By age 9 months, while sitting by themselves, infants should be able to self-correct posture when tilted to one side or the other, rather than just being tipped over.