Although Darus has not been formally diagnosed with hypotonia, AKA low muscle tone, I believe he has it, even if just mildly.  It was not noted at birth, nor was it noted by his developmental pediatrician upon our first visit in November 2012, nor was it noted by the geneticist in March 2013.  However, I have always wondered why his colds would last so long and why he was always chesty, especially as a toddler.  I now know.  Because his diaphragm isn't as strong as it should be.  I believe the hypotonia is also the reason why he drooled constantly the first 3 years of his life ... and intermittently since then.  Thankfully he's been quite healthy, physically.  And thankfully we've been taught how to perform Beckman stretches on his face, that have greatly helped to reduce if not extinct his drooling.