Now 3 in all ways?

My younger son recently turned 3 and has been very cognizant of the change. He has switched his favorite Thomas engine from Edward to Henry because Henry's number is "3". The other day he was in my room while I was dressing and he stepped on the digital scale.  (It read 29.8 lbs).  "Mommy, why doesn't it say 3?"  I guess he expects to measure 3 is all dimensions!