Hair color changes up until 2 years old. Chloe started out black with a little blonde then her head started getting a little silver. Now, at 13 months, her face has lightened up a lot compared to when she was a baby. Her face is mostly blonde now. Her back has recently started getting some silver strands, which I believe is also standard to become "blue" which in yorkie terms just means a diluted type of black. Trinket to me looks like she'll have the standard yorkie coloring, too. She also looks like she has a silk coat to me.
Chloe was about 1.5 lbs at 8 weeks and she did get a little longer and taller but not too much. I used the growth chart, also and it was pretty accurate for me. She is about 3 pounds now full grown. Her length and height stayed about the same since around 8 months old.
This is just my take on your questions.
