Answer by taking a quote from the following article:

Rachel Anne Summers (also known as Rachel Grey) is a fictional superheroine appearing in American comic books published by Marvel Comics. Rachel was created by writer Chris Claremont and artist/co-writer John Byrne. In her first appearance, the character's surname was not revealed; later publications and retcons further expanded her backstory to involve central characters of mainstream continuity. She is the daughter of the alternate future counterparts to Cyclops (Scott Summers) and Jean Grey-Summers from a harsh dystopia, the sister of Nate Grey and half sister of Cable, a niece of Havok and Vulcan, and a powerful mutant in her own right.

After Rachel was kidnapped, along with Cyclops, by her paternal uncle Vulcan, he freed Darwin from inside him. Later, Professor X recruited Rachel, along with Havok, Nightcrawler, Warpath, Darwin, and Polaris, for a space mission to stop Vulcan from laying waste to the Shi'ar empire. Xavier, who recently was stripped of his powers, recruited Rachel to serve as his telepathic "eyes and ears" during their mission. Aware of Rachel's vendetta against the Shi'ar, Xavier agreed to use their trip into space to find out who in the Shi'ar Empire gave the order to wipe out all members of the Grey family, and he warned Rachel that they will deal with the people responsible for her recent losses Xavier's way. While in space, the team was attacked by Korvus, a Shi'ar warrior sent to kill Rachel. Korvus' ancestor, Rook'shir, was a previous host of the Phoenix Force, and a small portion of the Phoenix's power was left behind in his sword, the Blade of the Phoenix. With this power, Korvus made short work of the other X-Men, but when Rachel blocked the sword, their minds were involuntarily linked. Through this link, Rachel learned that Korvus' family was also murdered by the Shi'ar government because of their connection to the Phoenix. The remaining echo of the Phoenix power from the sword was then transferred to Rachel. Rachel claimed that rather than having taken the power, the power chose to go to her, saying, "The Phoenix knows me, remember? It likes me." When this happened, Rachel's normally gold energy aura turned blue, the same color as the Blade of the Phoenix. She then telekinetically disabled an explosive implant that the Shi'ar chancellor was using to force Korvus' obedience. Due to Rachel's connection to Korvus through the sword, she discovers the Phoenix Force formerly in the blade is just an echo, a "blue shadow", of the Force. The shadow of the Phoenix begins influencing Rachel's behavior, causing her to design a new darker uniform and begin a romance with Korvus. She soon breaks off the relationship after she realizes their bond is only because of the residual Phoenix Force. Leading up to the fight with Vulcan, Rachel is shown using her powers to kill the guards who stand in her way. Havok warns her not to, but Rachel tells him that they deserve to die after what they did to her family. When it comes to the big fight, Rachel shows just how powerful she is by protecting Korvus from one of Vulcan's blasts. Rachel is one of the X-Men stranded in Shi'ar space when their ship is sent back to Earth. After the death of her other grandfather, Corsair, at the hands of Vulcan, she, along with Havok, Polaris, Korvus, Ch'od, and Raza, become the new Starjammers. They elect to remain in Shi'ar space and restore Lilandra to the throne or die trying. As her uncle states, "If they fail, he has no doubt that Vulcan will head for Earth." CANNOTANSWER

How was she freed?

CANNOTANSWER