Also, Doppler can detect abnormal blood flow within the heart, which can indicate a problem with one or more of the heart's four valves. Color Doppler. Color Doppler is an enhanced form of Doppler echocardiography. With color Doppler, different colors are used to designate the direction of blood flow.
(I got armpit hair around 11 1/2 but everyone is different) From around age 13-16 but it can still happen earlier or later (maybe even 12 and 19) got mine just before i turned 14. Brent Lyday.
But around age 8 or 9, most kids start needing to scrub up daily, since it's usually around this time that they begin sweating and experiencing odor from areas like their armpits, feet, and private parts. Girls are especially vulnerable because they typically start puberty a year ahead of boys.