I feel she's filtering it because she can't have any aspect of her life being anything other than (her version of) perfect. Like how she filtered Mad Mick's hair for so long everyone genuinely thought he was blonde and not ginger. Because a blonde haired child was more what she wanted, clearly.
Kids get cradle cap. My eldest never had it, the younger one had it pretty badly. I regularly oiled his scalp, carefully combed his hair daily and it helped a bit, but it still came back on and off til he was maybe 2 or 3. On the plus side he did end up with a beautiful head of hair, not sure if the 2 are connected!
She doesn't have to mention every aspect of her kids lives, but as she does overshare a load of other nonsense, why not say 'you might have noticed Roess has cradle cap, it's completely normal, we've done this or that, this thing has helped, this thing didnt, etc' but she's not done that because it shows a less than perfect aspect of her life.
Also because there's nothing in it for her financially. If it doesn't bring in the £££s she won't mention it!