He is sooooo cute! Adorable! I had straight hair until I was almost 5 and the it turned wavy and about 6 years later VERY kinky and curly all the way to a 3b. My cousin who is also biracial had curly hair that got straighter as she grew older.
So I think its hard to say what he'll eventually be. My mom just washed my hair, conditioned and would just comb in leave in conditioner. Kids hair is supposed to be kinda messy anyway. Like the other poster siad just don't use anything drying! A lot of those detangler products can be.
They should should stop cutting it and let it grow longer. I love the heads with lots of curls on boys. I think he look cute with the fro!