Magda (Hidden Human History)

Magda was a young woman who lived in Guelder in the 1500s.

After she ran into the Thirteenth Doctor (quite literally in her case) and Team TARDIS, she told them of the mysterious "demons" terrorising the townspeople. An investigation by the Doctor revealed these creatures to be Stilean flesh eaters and, upon seeing them, Magda rang the village bell to warn everyone.

She had an uncle, and was illiterate. (COMIC: Hidden Human History)

Behind the scenes
Magda erroneously makes an additional appearance alongside the Thirteenth Doctor and Yaz when Leon Perkins and Irene Schulz appear, despite Team TARDIS having left her native time period by this point.