Uley Pack

The Uley Pack, most commonly known as the pack or Sam Uley's pack, is formed when Sam Uley first phased into a wolf, the occasion of his coming-of-age in the presence of the Olympic Coven: a coven of vampires. Over time, Paul Lahote, Jared Cameron, Embry Call, Quinn Swan and Jacob Black also phase and Sam took responsibility for them. Their pack was later joined by Seth and Leah Clearwater, Quil Ateara V, Brady Fuller, Collin Littlesea, Maynord Morris. After Jacob, Embry, Leah, Seth and Quil broke away from the pack, it was joined by seven unnamed members.

History
The pack was formed in the year of 2004 when Sam started phasing, becoming the first of his generation to become a wolf, and later Jared and Paul. To protect other people from harm, they are all forced to keep themselves at a distance to protect their mutual secret.

New Moon
In New Moon, they avert their first crisis, when they kill Laurent in New Moon, who attempts to kill Bella for sustenance, and chase away Victoria. By now, there are six members in the pack: Sam Uley, Jared Cameron, Paul Lahote, Embry Call, Quinn Swan and Jacob Black.

Bella mistakes Sam for having forced Jacob into his group and murdering people in Forks and La Push, until Jacob tells her it was the work of a vampire and that they have been trying to stop the murders, and that their magical genes have been set off by the presence of vampires.

When they later learn that Victoria is after Bella, the pack works to protect her and Charlie while chasing away the vampire.

Eclipse
In Eclipse, the pack has grown to ten, with the addition of Quil Ateara, Leah and Seth Clearwater, Brady Fuller and Collin Littlesea. When a nomad infiltrates Bella's house only to steal a red blouse with her scent, the Cullens suspect that someone is orchestrating a plan and form allegiance with the pack to protect Bella and Charlie.

Hearing that an army of newborn vampires led by Victoria and Riley are on their way to Forks, Sam's pack agrees to co-operate with the Cullens against the army, after the Denali Coven refused to aid them. The battle is a success, with Jacob the most injured in action saving Leah from a hiding newborn.

Breaking Dawn
The pack splits in Breaking Dawn, following Jacob's and, later, Seth's and Leah's departure to protect a pregnant Bella and the Cullen family from them. With three members less, Sam confides in the Quileute council and come to conclusion that they wait till Bella's baby is born to make their move. However, Jacob imprints on the baby, Renesmee Cullen as soon as she was born, and the wolves are forced to declare permanent peace with the Cullens to keep the two packs from warring each other. A few months later, Embry and Quil also join Jacob's pack, something they weren't able to do previously.

During the Volturi's trial, the pack (which by now had grown to twelve members) stands by the Cullens and their witnesses, ready to fight if battle ensues. During this confrontation, they find out from Edward and Aro that they are not real werewolves, but a group of a shape-shifters with the ability to turn into wolves.

Members
This pack consists of Sam Uley (Alpha), Alex Swan (Beta), Paul Lahote (third-in-command), Brady Fuller, Collin Littlesea, and by the end of Breaking Dawn seven more unnamed members.

Jacob Black, Seth Clearwater, Diamond Romano, Leah Clearwater, Leah Dakota Clearwater and Scott Macdonald run off when Sam decides to kill Bella and her unborn baby. Not wanting to fight his own kind during Renesmee's crisis, Sam declares a truce between the packs and decides to watch the Cullens until after she is born to decide if she is a threat or not. However, Jacob's imprinting on the baby forces Sam to re-evaluate the decision and permanently declare peace with the Cullens to prevent unwanted conflict. After the tension between the two packs resolves, Embry Call and Quil Ateara V leave to join Jacob's pack.

According to The Twilight Saga: The Official Illustrated Guide, Paul is also the third-in-command.

even new members are very young.