Gertie (Super Gran)

From Tardis Wiki, the free Doctor Who reference

Gertie was a companion of the Twelfth Doctor.

One of Gertie's adventures took place on Mars, during its earlier stages when it had water and thriving plant life. She explained to her grandson Charlie Baker that it was peaceful and quiet, until something interrupted them.

Once she encountered a Gestalt Creature which attempted to superheat the planet's surface and destroy all life.

Another time, the Doctor took her to the past to see a pyramid, yet they were attacked and chased by a mummy.

In 1986, the Doctor dropped her off on Earth and told her he'd be back at 26 September, but he didn't specify on which year he would return. She waited 30 years until 2016, when the Doctor arrived with Clara Oswald on a Time dragon. He then took Gertie and Charlie on an adventure to Mars. (COMIC: Super Gran)