Wayward Son

Acquisition
Hawke will either encounter an elf of Dalish heritage who is talking to an templar at the Elven Alienage, who is looking for her son, Feynriel, who has disappeared, or Hawke can also receive this quest from the Templar Thrask in the gallows district. It appears Hawke must complete the Long Way Home quest before this quest will activate.

When talking to Trask with Aveline in your party, referring to her directly results in.

Walkthrough
Feynriel is the son of an Dalish elf living in the Elven Alienage and a human merchant. He also has the talent for magic, something his Dalish mother hid out of fear of losing him to the circle until his nightmares could no longer be ignored as a warning signal.

If Hawke gets the quest from Arianni then the dialogue options "I will stop him" followed by "Don't hold your breath" result in

Talking to Thrask after getting the quest from Arianni can result in, if you have her convince Thrask. Saying that you want to help Feynriel earns and, while saying that the boy is a menace earns.

Depending on who gave the quest, Hawke will either seek out Feynriel's father if the quest giver was his mother and then be directed to a retired templar named Samson or be sent directly to Samson if Thrask gave the quest. Samson is a retired templar, who resides in Darktown and supposedly helps runaway apostates.

But Thrask could not help Feynriel since the boy could not pay for his passage and instead sent him to someone who might give him free passage. Samson will tell Hawke to go check out the Docks. Upon arrival the party is ambushed by Redwater Raiders, which are easily dispatched.

Upon entering a private docking area, the party is ambushed by a group of slavers. After defeating them, Hawke walks in on a mage in mid transformation into an abomination. After dispatching the enemies, Hawke located a bill of sale directing the player to another group of slavers.

After defeating them in a far corner of Darktown, the player will find a map in a chest directing them to the Wounded Coast, into a slavers den. If Fenris is in your party, Hawke can use him to make the slaver give him the information without a fight. , if Hawke then lets the slaver live. Having Fenris make Danzig talk and then kill him results in with Fenris,  with Carver and  with Aveline. No change to Isabella, Varric, Anders or Merill.

After several tough battles including mages and Qunari, Hawke will walk in on the leader of the slavers who is holding a sword to the throat of Feynriel. Hawk can choose to bribe the slavers and pay for Feynriel's release. Alternatively, he can also choose to initiate a cut-scene in which he kills the leader with a throwing knife, thereby eliminating him from the following battle making things much easier. Also, if Varric is in your group, you can choose to have him speak to the leader and convince him to release Feynriel without a fight, gaining 3 in the process.

After the fight Hawke can opt to convince Feynriel to surrender to the Circle of Magi for his own good, or he can allow him to go live with the Dalish clan in the mountain, either way. Hawke is then directed to go tell Feynriel's mother of his fate.

Hint: After the dialog with Feynriel don't leave the cave through the near exit, instead go back through the cave to the entrance for a fight against some spiders, giving you some XP.

Result
Feynriel will either go and live with the Circle or with the Dalish clan depending on Hawke's choice.

Allowing Varric to speak to the leader gains:

Killing the slaver leader (Varian Ilithis) grants:

Letting Varric speak to the leader, and still kill him afterwards grants:

No impact on Aveline.

After the fight, you can choose to send Feynriel to the Mages Circle, or letting him live with the Dalish.

Convincing him to go to the Circle has companion effects:


 * (not confirmed, only the above speak option gives +5)
 * (not confirmed, only the above speak option gives +5)
 * (not confirmed, only the above speak option gives +5)
 * (not confirmed, only the above speak option gives +5)
 * (not confirmed, only the above speak option gives +5)
 * (not confirmed, only the above speak option gives +5)

No impact on Isabela

Sending him to the Dalish has companion effects:


 * (only with the "you deserve to choose for yourself" option)
 * (only with the "you deserve to choose for yourself" option)
 * (only with the "you deserve to choose for yourself" option)
 * (only with the "you deserve to choose for yourself" option)
 * (only with the "you deserve to choose for yourself" option)
 * (only with the "you deserve to choose for yourself" option)

Rewards
Runed Silverite Ring & some coin. If Circle option was chosen, then; Anders: rivalry (+5) upon receiving reward.

Crafting Nodes
Inside the Slaver caves you'll find a Spindleweed node and a Deep Mushroom.

Trivia

 * Upon finding the map to the slaver den in the chest in Darktown, a sarcastic/witty Hawke may make a joke about the Wounded Coast, saying it must be near other locations that have the words 'injured' or other similar words in their name.