Who are the sixteen bastards of Robert Baratheon?

Question

Who were the sixteen bastard children of Robert Baratheon and what were they doing before they died? Except Gendry who escaped getting killed on the order of King Joffrey and ran off with Arya Stark.

Answer 1

A Wiki of Ice and Fire names five and lists two unknown twins:

Although Robert Baratheon is known to have fathered - according to Maggy the Frog's prophecy - a total of sixteen bastards, only one has been acknowledged. Varys admits to knowing of eight. Five have been seen by point of view characters, while two others have been mentioned only in passing. Because of how Eddard words Robert's will, Cersei begins a campaign to kill all of Robert's bastards, but Tyrion stops it after an ugly scene with Barra's mother fighting to protect the baby. They are listed in approximate age order.

• Mya Stone. A bastard daughter born to Robert in the Vale whilst he was Jon Arryn's ward. She serves as a guide to and from the Eyrie, and becomes a favorite companion to Sansa Stark. Eddard Stark remembers that Robert was very fond of her, although like all his bastard children he later abandoned her.
• Bella. An unacknowledged bastard daughter who lived at the brothel called the Peach in Stoney Sept. Her mother told her that she was conceived during the Battle of the Bells when a wounded Robert hid there.
• Gendry. An unacknowledged bastard who was born to a worker in an alehouse. When he was old enough, an unknown lord paid Gendry's apprentice fee so he could learn to be a blacksmith. Gendry developed a reputation for stubbornness and fashioned a bull's head helmet, causing him to be named "the Bull". Following the death of Robert, Varys arranges for the boy to flee King's Landing with Yoren of the Night's Watch. Gendry knows that Queen Cersei wants him dead, although he does not know why. He travels with Arya Stark until the Brotherhood Without Banners captures them and he joins the organization. The Brotherhood later places him at the crossroads inn to smith and look after a group of orphans there. When Brienne of Tarth meets him, she is astonished by how much he looks like Renly, actually addressing him as "Renly" and "my lord".
• Edric Storm. Robert's only acknowledged bastard son, born to Delena Florent. He lives at Storm's End under the protection of Cortnay Penrose, the castellan. Robert visited Edric almost every year, taught him how to fight, and gave him a warhammer. Stannis lays siege to the castle with the goal of capturing Edric Storm and using him to prove his claims of Cersei's incestuous affair with her brother Jaime. The red witch Melisandre also aims to use Edric's blood to raise the dragons of Dragonstone. Davos Seaworth smuggles Edric away from Dragonstone before he can be sacrificed and he is taken to Lys.
• Two unnamed twins. Petyr Baelish hints that Robert fathered twins to a serving woman at Casterly Rock who were killed by Queen Cersei's agents.
• Barra. The youngest of Robert's known bastard children, born to the King's Landing prostitute Mhaegen. A baby, Barra is killed by Allar Deem under Cersei's orders following the death of Robert.