Yes, GSM but do you, your DH, DC/DGC all wear the same colour when out together? This is the aspect which puzzles me.
We all have favourite colours/patterns/fabrics/styles, that is how our individual style is defined, but extending that to your children and DH really is - unusual.
I am one of three girls, and my mother went through a stage of dressing us alike - I was 6 1/2 years older than my youngest sister, you have no idea how embarrassing/ infuriating etc it was when I was 10-12 to be dressed the same as my 4-6 year old sister.