Gliding Raptors

Jurassic world is right now dead, so I'm going to bring it back to at least a zombie state. This is a strange idea, but I'm wondering if most young Dromeaosaurs could glide. We know Miroraptor and probably Sinornithosaurus could as adults, but besides that, it doesn't seem like any others could glide. As adults. What if sub adults or older juvenile raptors developed flight feathers and could glide? We know that Unenlagia as an adult had flight feathers , so why doesn't a sub adult or juvenile have them too. They could be light enough to be able to get off the ground, and it would make them safer from predators. What do you think?