Most people don’t place conditions on their children’s love. A simple “I love you” is enough on its own, it shouldn’t need justification, because a parent’s love is meant to be unconditional.
Compliments can be given separately. When she says she loves them because they’re brave or kind, it raises the question to an impressionable child: if they stop being brave or kind, does her love disappear too?
It’s just clumsy execution yet again. She could make two clear, seperate statements (“I love you” and “You are kind/brave”) to convey both messages. Putting them together makes the affection sound transactional, as though her love depends on their behaviour.