i have a 1999 lumina and both of the backdoor windows only go 1/2 way down. why??

 

I know a lot of chevys in the late 90s early 2000s have child safety windows. My moms old 2000 2500 crew cab the back windows would only go half way down. I wanna say there was a switch in the door that would let them go all the way down dont hold me to that though.