I'm attaching several PNP fellowships to this post. I'm just another student (FNP) graduating in May 2019. I've been interested in the idea of a fellowship/residency after graduation, and have spent quite a bit of time looking at many. However, I don't have any personal experience with these fellowships, so take what I have with a grain of salt! Good luck to you!
Seattle Children's APP Fellowship (Washington, lots of detail about their program, "prefers Acute Care")
Advanced Practice Provider (APP) Fellowship Program
Nemours Pediatric APP Residency (Delaware, Not much detail about their program)
Pediatric Advanced Practice Nursing Fellowship Program | Nemours
Wyckoff NP Pediatric Fellowship (New York, not much detail, odd start time [March 2019])
NP Fellowships : Wyckoff Heights Medical Center