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.
Shaving is a big deal to many boys and they look forward to it, even if they have to wait a while for puberty to catch up with them. Most boys won't develop facial hair until they're well into puberty (generally around age 14 or so), while others may need to begin shaving in the later tween years. Either way, arm yourself with a few handy shaving tips to help your child learn to do it the right way.