Though inspired by the Carstairs family from the shadowhunter world (by Cassandra Clare), the crest is made for a different purpose.
On a minecraft server named Potterworld, I made a roleplay family named the Carstairs and made a crest for the family. This is it, however it is still a sketch.
I did do a bit of research for the chosen symbols.
The castle stands for safety and protection.
The helmet stands for wisdom and security in defense; strength, protection, invulnerability
The Vol (set of wings) stands for swiftness and protection.
The colors I have still not chosen and I also hope that one day, I can possibly make a better version and also in colour.