how does this hair develops?
It develops on fetuses as a normal part of gestation.
Lanugo
During human development, the lanugo grows on fetuses as a normal part of gestation, but it is usually shed and replaced by vellus hair at about thirty-three to thirty-six weeks of gestational age.
what is reactive attachment disorder? It is a severe and relatively uncommon disorder that can affect children. what causes it? It is based on a problematic history of care and social relationships. can it be diagnosed? It can olny be diagnosed by a psychiatrist and any assessment must include a comprehensive evaluation of the child's individual and family history. what are some of the symptoms? Infants up to about 18–24 months "may" present with non-organic failure to thrive and display abnormal responsiveness to stimuli. The core feature is severely inappropriate social relating by affected children. can this age group travel on plane? Many airlines refuse boarding for all babies aged under 7 days (for domestic flights) or 14 days for international flights. what kind of hair do they have? A fine, downy body hair called lanugo. can you find this hair in animals too? Yes, animals like seals and elephants too are born with this.
wiki:18008937
Lanugo [SEP] Fetal development
During human development, the lanugo grows on fetuses as a normal part of gestation, but it is usually shed and replaced by vellus hair at about thirty-three to thirty-six weeks of gestational age. As the lanugo is shed from the skin, it is normal for the hair to be consumed by the developing fetus, since it drinks from the amniotic fluid and urinates into its environment. As a result, lanugo contributes to the new-born baby's meconium. The presence of lanugo on new-borns is not necessarily a sign of premature birth, as it also seen on infants born at thirty-nine weeks of gestation (full term).