Coven of Spirits.

There are families of witches that go back for generations upon generations, each of their members devoting their lives to the study of witchcraft. Their devotion to the craft changes their very blood with each passing heir until the art of witchery is in the very veins of all those born under the branches of those family trees. They are called Witch Sorcerers.
Witch Sorcerers have witchcraft in their lineage, and their powers reflect this. The spirits of their ancestors watch over them at all times, and empower them in ways that are not available to any other magic practitioner, allowing them to weaken or strengthen magic around them, and cheat death itself. Their power, however, comes at a price, as their ancestors watch over the sorcerer’s every move, forever judging their actions and ensuring that the interests of the family remain their top priority. It is up to the witch sorcerer to decide if they will forge their own path.

Witchmark.

Witchmark for sorcerers are passed down from parent to child with little divergence. They are unique to every witching family, and often look like the family crest. Witching families are generally proud of their ancestry, and their witchmarks are often displayed prominently on their bodies, in places like their face or their hands.

Level 1 Features:

Ethereal Coven.

When you choose this origin at 1st level, you can project your consciousness into the Ethereal Plane while dreaming to seek the counsel of your witch ancestors.
During a short or long rest, you can transport your consciousness into a safe pocket plane where you and your ancestors can meet while you sleep. When you meet them, you effectively ask the same questions as the Augury spell. You can also use this time to converse for a short while with them, what they tell you being at the discretion of the GM.
At level 10, your bonds with your ancestor strengthen, you can now effectively ask the same questions as the Commune spell.
Your ancestors watch your every move, and might not choose to respond at all when asked depending on your standing with them.

Favoured Heir.

At 1st level, the spirits of your witch ancestors protect you and those you love from death. When you or a creature you can see within 60 feet of you rolls a failure in a death saving throw, you can spend 1 sorcery point to reroll that death saving throw. Additionally, if you roll a natural one on a death saving throw, it only counts as one failure instead of two, and any attacks that would automatically make you fail two saving throws only make you fail one.

Level 6 Feature:

Weakening Spirits.

At 6th level, you summon the spirits of witches in your bloodline to weaken spells cast against you or your friends. As a reaction and by spending 2 sorcery points, you can weaken a spell that requires a saving throw targeted at a creature you can see, the creature adds your Charisma modifier to their saving throw.
Once a creature has benefited from this feature, you can’t use this feature on that same creature until you finish a short or long rest.

Level 14 Feature:

Emboldening Spirits.

At 14th level, you summon the spirits of witches in your bloodline to empower your spells. When you cast a spell requiring a saving throw from the target, you can spend 4 sorcery points to add your Charisma modifier to your spell save DC a second time.
Once you’ve used this feature against a creature, you can’t use it against that same creature until you finish a short or long rest.

Level 18 Feature:

Shield of the Coven.

At 18th level, the spirits of your witch ancestors stand proudly at you and your allies’ side, protecting you. As a bonus action you can spend 4 sorcery points to summon the spirits of your ancestors around one non-hostile creature you can see that your ancestors would approve of, at the GMs discretion. That creature gains an AC bonus equal to your Charisma modifier for 1 minute.
Once you’ve used this feature on a creature you can’t use it again on that same creature until you finish a short or long rest.