From Bulbapedia, the community-driven Pokémon encyclopedia.
Madame Boss (Japanese: 女ボス Lady Boss) is a former leader of Team Rocket and the mother of the current leader, Giovanni.
She is certainly not as smart as her son, Giovanni. This can be based upon numerous facts, including her reaction to hearing a recording proving the existence of Mew, a creature that could bring Team Rocket immense fortunes. She responds with the quip "Can we make a CD out of it?" Her primary focus seems to be on making money. However, she is an effective leader and does not show true ineptitude at her job.
Relationships with other members
As Rocket Boss, she commands an army. She gives direction to Miyamoto personally, and speaks of her 'brat boy' Giovanni. Going strictly by the timeline presented by the CD drama, he would have had to be at least twenty years old at the time she said that, which proves her relationship with him to be at best extremely hostile.