It's real, but it's not a phenotypic mutation - that means that it's not a mutation that affects feather colour. This budgie type is called chimera, when there is an improper division of the embryos during development and one half of the budgie has one type of DNA while the other half has another It's almost like Siamese twins, but completely indistinguishable anatomically. These birds have the DNA of two birds in them, which is pretty cool! It's an extremely rare occurrence
and Princess Mallorn!
Thank you to Deb for her wonderful Faery magic