Silas Heap is a seventh son of Ben Heap, a talented shape-shifter, yet he himself is a not-so-competent Ordinary Wizard who lives in The Castle. He is married to Sarah Heap and is the father of Septimus Heap, Jojo, Nicko, Edd, Erik, Sam and Simon Heap. He is also the adoptive father of Jenna Heap. Silas was born the day that DomDaniel fell off the roof of the Wizard Tower. He was apprenticed to Alther Mella, but asked Alther to annul his apprenticeship so that he could live with Sarah Heap. Silas lived in The Ramblings until Jenna discovered that she was the Princess and went to live in the Palace .
Silas Heap was born as the seventh son to the Shape-Shifter Benjamin Heap and Jenna Crackle. He had six brothers: Alfred, Hengist, Louis, Ernold, Edmond and Garth. The Heap family was a Magykal family that included his aunt and White Witch Zelda Zanuba Heap and his uncle, Theo Heap, who turned into a storm petral and never returned. As his father, Benjamin turned into a tree when Silas was young, and went to live in the Forest, leaving his son looking for him.
Silas pursued the family profession and became apprenticed to Alther Mella, the ExtraOrdinary Wizard. But while being the ExtraOrdinary Apprentice, Silas fell in love with Sarah Heap, and, after starting a family, decided to resign form the ExtraOrdinary Apprenticeship, a job that was to be filled later by Marcia Overstrand. Sarah gave birth to seven boys, all with blonde curls and green eyes, and they later adopted a daughter, Princess Jenna, when they were told that their seventh son had died.
Silas was taking a late walk after the supposed death of his seventh son, Septimus. He was gloomily making his way back to his cramped home in the ramblings when he sensed a soft crying. He made his way to the group of bushes the sound seemed to be coming from and noticed a small bundle who he later discovered being princess Jenna. He took the baby home and was confronted by a flustered Marcia Overstrand, who instructed him to tell no one he'd found her and pretend she was born to his family. He raised Jenna with his wife as their own.
Jenna's identity revealed
Ten years later, Marcia returned to the Heap residence explaining that Jenna was in terrible danger and she, Silas, Maxie, Jenna, and Boy 412 ran to Zelda Zenuba Heap's cottage. There he recived a message from Stanley, the Message Rat informing him that his eldest son, Simon Heap had disapeared. He headed to the castle in search of Simon and failed in his search, then fell into a temporary morose state until the ghost of Alther Mella informed him that Simon attempted to elope with Lucy Gringe but was caught by the Custodian guard who had kept him prisoner until his recent escape. They then rushed to the hole in the wall tower were they found Simon with several ancient ghosts. Silas then departed with Sarah, Simon and Alther, trying to reach the Port to escape to the far countries as DomDaniel had returned with a particular hatred for the Heaps. However he stuck his foot through the boat, which was eventually repaired. Silas then returned to Aunt Zelda's for Boy 412's apprentice supper where he discovers that Boy 412 turned out to be Septimus, and reclaimed his seventh son.