They will grey, and if you look at older V's it's somewhat shocking, their entire muzzles and all feet to the pasterns ("Wrists/elbows") are totally white. That happens slowly over time, so anything past 3ish it can start.
The worry with premature white (and yours doesn't qualify based on that cute pic), is some autoimmune disorder. That usually has other, far more serious (and noticeable) symptoms, so if your V is active and healthy otherwise with no signs of distress then it's just...life. Drink it in, they are with us for such a short time, this is just a reminder to cherish every moment.