Some children, my oldest son comes to mind, progress at their own rates. My mom use to tell me not to compare him to others that he was on his own trajectory. I kept detailed journals so I could look back and cheer him on with how much progress he had made. He walked early, but talked late, potty trained late, had trouble learning to read, was hyperactive, and on and on....... It often seemed he took one step backward for every step forward. He finally started sleeping through the night and seemed to forget he was toilet trained. He'd learn to zip his coat and suddenly couldn't remember how to velcro his shoes. He didn't tie his shoes until he was almost ten. He is the reason I started to home school so I could constantly readjust his schooling. We did everything possible to maximize his independence and encourage him to socialize and learn critical thinking skills. It was often hard and discouraging. So many times I called my mom crying...... But and this is a huge but...
He is a teenager with a wide range of opinions, interests, and friends. He on track academically, except for writing, the child hates to write. He has plans for his future (maybe not the one I envisioned when he was a baby). He wants to be a vet tech, learn to drive a car, rent an apartment with his best friend and raise snakes. He falls in love every other week, lives to play RPGs with his friends, and regularly argues with his dad and I about all teen age things. He volunteers at an animal shelter, has good relationships with his family, and plans to marry and kids some day. I never imagined at 3 or 5 or even 8, his future would be this bright. He may never obtain a 4 year degree or make lots of money but this is light years beyond the future a doctor once gave us where he would never be able to live independently, drive, make friends, or even read at a 5th grade level.