So let us the meet our first trio of subjects, first with Lugia's ladies!

Zapdos
Gender: Female
Current Residence: Power Plant, Kanto
Nature/Characteristic: Brave / Likes to fight
Movepool: Discharge - Drill Peck - Rain Dance - Thunder

Moltres
Gender: Female
Current Residence: Victory Road, Kanto
Nature/Characteristic: Hardy / Takes plenty of siestas
Movepool: Flamethrower - Sunny Day - Solarbeam - Sky Attack

Articuno
Gender: Female
Current Residence: Seafoam Islands, Kanto
Nature/Characteristic: Mild / Capable of taking hits
Movepool: Ice Beam - Hail - Blizzard - FreezeDry

Zapdos, Moltres (btw her eyes are like that, anime thing) and Articuno are the highest ranked subordinates of Lugia and just like him, they wear shades: customized Scope Lens! Though they live far away from each the other (Moltres is constantly changing of residence), they spend most of the time together in their master's residence, mostly for fun and games. Musical games in special, they share the same passion for music as him! In such way most of the times they open the beak is to spell lyrics of whatever music instead of ordinary speech.
Individually, Zapdos is more into rap and hip-hop, while Articuno likes traditional music from different regions such as samba, fado and others and Moltres prefers rock and heavy metal. But together they just sing whatever comes to mind that suits what's going on. In short they are Lugia's background music. If you follow their game they immediately let you join and sing along but if you be a grump about it, they will pinch worse than any Tri Attack :3

That's all! Moltres's nomadic habit is a tribute for that strange tendency of GAMEFREAK by changing it localization every single game :3 And the fact all three birdies roamed in Kalos in XY? Maybe there's a reason for that huuuh