The Sapling

The Sapling was a sapling of the Planting whose development was interfered with by the Scream. Infused with some of the memories of the Eleventh Doctor and Alice Obiefune, the Sapling renounced his destiny as an organic super-virus capable of genocide and instead tried to follow the example set by his "progenitors": the Doctor and Alice.

The Sapling accompanied the Doctor and Alice in their adventures through time and space. During this time, they were followed by the Scream.

Creation
After the Planting seeded itself in a desert planet and replaced all indigenous life with a forest of itself, it created the Sapling with the intention of sending the Sapling to a different planet to do just the same. However, the Scream captured the Sapling in a Memory Engine Machine during its formation. The Scream planned to feed the Sapling with the memories of several long-lived individuals and then use the large amounts of memory energies to merge himself with the Sapling and become part of the sentient ecosystem of an entire planet.

The Scream's plan was fairly successful up until the end. (COMIC: The Scream) He managed to feed the Sapling the full memories of a Nebulon and a Rockra, (COMIC: Remembrance) and some of the memories of the Eleventh Doctor and Alice Obiefune. While the Sapling was absorbing the memories of the Doctor and Alice, the Scream came inside the Memory Machine to merge with it. The process was disrupted when Alice caused the Doctor's TARDIS to materialise around the machine. The TARDIS saw that the Scream was dangerous and deposited him outside, leaving the Sapling to grow into a sentient child-like being inside the Memory Machine. (COMIC: The Scream)

Adventures with the Doctor and Alice
After the Doctor and Alice escaped the Scream and briefly reunited with John Jones and the Entity, they returned to the TARDIS and met the Sapling for the first time. Having many of their memories, the Sapling was already intimately familiar with their lives. Due to his nature as a biological weapon capable of genocide, the Sapling asked the Doctor to destroy him, but the Doctor refused. The Doctor and Alice instead took on the Sapling as a companion. (COMIC: The Scream)

The first place that the Sapling visited with the Doctor and Alice was Hackney in the early 21st century to pop in to Alice Obiefune's flat. However, they discovered that the Wayfarer had landed on Earth in 1968 and was sucking up the planet's time, destroying the barriers between years. Allying with many versions of Kushak, the Doctor, Alice, and the Sapling journeyed from the 21st century to 1968 in a double decker bus. The Sapling used the sonic screwdriver to vibrate the wall surrounding 1968 errected by the Sixty-Eighters, creating a hole. When the Wayfarer prepared to drain the Doctor and Alice of their time, the Sapling did the only thing he could think of to stop the Wayfarer: he began seeding himself into Earth, setting in motion the irreversible biological processes which could replace all life on a planet with forest. However, after the Wayfarer was killed by the Sapling, time was restored to Earth and all events involving the Wayfarer were rendered as having taken place in a temporal anomaly, meaning that they were undone. (COMIC: The Tragical History Tour)

The Doctor took Alice and the Sapling to Plex's planet, where they found its inhabitants to be at war with each other. In the ruins of Plex's laboratory, the Sapling extended the length of his arms to grab Plex's biodata module for the Doctor. The Doctor used the nodule to restore Plex's memory to one of the clones of Plex, elevating the clone to be a god among his people who would lead them into a new period of peace. (COMIC: The Promise)

During a game of chess with Alice in the TARDIS, the Sapling's mind was touched by Ood Sigma; Sigma channelled a message to the Doctor through the Sapling: "Bring them home. Share the Song." The channeling put the Sapling into mental lockdown, rendering him unconscious. The Doctor and Alice left the Sapling to recover in the TARDIS while they investigated why the Devil's Eye still used Ood as slaves. When the Doctor lowered the shielding of the Devil's Eye, Alice put the psychic paper and Jonni Halburton's data-slice onto the Sapling's forehead, using his unconscious body as a conduit between Ood Sigma and the Ood of the Devil's Eye. The Sapling then woke up. While visiting the Ood Sphere with the Doctor and Alice, the Sapling built a Fourth Doctor snowman. (COMIC: Time of the Ood)

Shortly after leaving the Ood Sphere, the Doctor parked his TARDIS in the Antrozenus Zone to get some time to talk with the Sapling one-on-one about the "arboreal-eruption-slash-sacrifice-yourself-slash-almost-kill-everyone thing" the Sapling did to defeat the Wayfarer. The Sapling compared what he did to the sacrifice the Doctor made to end the Last Great Time War. Their conversation was interrupted when a Xerxes Memory Ark drifted near the TARDIS. The Sapling, Alice, and the Doctor boarded the Ark and repelled an infestation of Thrake. (COMIC: The Memory Feast)

The TARDIS trio went on a "shopping trip" to a European village in 1189 which involved them meeting an "old friend" of the Doctor who tried to kill the trio with a legion of archers. During this adventure, the Sapling accidentally became a well-known figure in the village's history, inspiring them to create a statue of him in the village green.

Shortly afterwards, they revisited the village circa Alice's home era and spent an afternoon at the Village Green Festival. Festival-goers assumed that the Sapling was wearing a costume to imitate the statue. However, even this trip was not without a malign alien influence: a Krovian tried to steal some of the Sapling's memories with a Memory Trap, but instead transferred all the memories it had already stolen into the Sapling's mind. This initially went unnoticed, but the Sapling came to realise that he could remember elements of the lives of other people at the festival which they themselves had forgotten. The Doctor tracked down the Krovian and destroyed the Memory Trap, removing the memories from the Sapling's mind and returning them to their rightful owners. (COMIC: Fooled)