Pictures of Camille and her sister show Camille reading a book in a dark dress while her sister is in light colors shorts playing in the dirt this shows that their parents are both Severin and Leroux, with Camille taking after her mother and her sister taking after her father.
When Camille gets her father's spellbook, she comments that she thought only women could do magic. Athalie constantly talks about what a selfish matriarch Camille's mother was, and tells her to wish for what they're told. Word of God confirms that Kalen Leroux is a trans man and Camille's mother used her wish for his transition.
Word of God states that the reason Camille gets along so well with Rowena Leroux is because she reminds her so much of what her late sister Chloe was like.
Seems very odd when you realize Severins usually have twin daughters and Avaline is the only one who doesn't have a sister along side her (sans Camille's case) and then we learn that Athalie is behind that. As she sacrificed one of her daughters to kill her sister's family via the wish to made to the demon she summoned during the 2nd ritual.
As Silvia explains to Camille and later Raum, the demons that are summoned, reflect the heart of the witch, Dendro is a reflection of Camille's mixed heritage, feeling different in their respective families, Raum is a reflection of Avaline wanting answers/the truth as stated. Meanwhile Strix is a reflection of Athalie's hatred in her heart, and willing to go to the point of murder.
Someone in the Webtoon comments section puts this well, pretty much when Athalie starts eating souls and turns into some sort of monster that's hungry for more, she becomes a living embodiment of the old Severin tradition: the endless hunger of it all. They lure in rich men to make money by pretty much using their daughters as bait in order to do it and demand more to maintain their wealth and status for generations. Effectively consuming both in the process, creating a cycle of one generation eating another, to keep the money flowing to the Severin family.
When Camille has to stabilize her magic it makes sense she starts it off by reaching out to Avaline, who is a representative of her Severin magic. Along with the fact that she does it in such a way that her mother couldn't reach out to her sister, Athalie, breaking that harmful cycle of Severin siblings being pitted against each other (since even if Camille and Avaline are cousins, they have a bond much like sisters due to losing a sister themselves, along with being under the same abuser(s)). And when doing so, that's when Camille can start hearing Toben's voice again. Then, when it came to the magic stabilizing ritual, Camille talks to her mother the longest, since she also is another representative of her Severin magic, the magic side that Camille needs to accept to heal and move on. She briefly gets to see and talk to her sister and Father, due to the fact that she already accepted the LeRoux side of her.
The stabilization ceremony seems to have only been used for trans/nonbinary witches before Camille because the only witches seen doing it before her in flashbacks aren't cisgender. Jazmin is a trans woman, Rowena and Sloane are nonbinary, and Kalen was a trans man. It was probably used to properly remove Kalen's magic, stabilize Sloane and Rowena's, and give Jazmin magic.
