Dd1 is 14, dd2 is 12.
Both have smartphones. Dd1 is very sensible and self-controlled about using it which is why I haven't imposed any particular rules. Dd2, however, gets irritable the more she uses it, it affects her mood, she's easily distracted, which is why I want to impose stricter rules about phone access. Dd2 complains this is the height of unfairness - is it?