Two comments, both of which are kinda-sorta on topic.
1. I did have a co-worker for many years who had a developmentally-delayed daughter when I worked at a museum. She (mom) would use the handicapped placard even when her daughter wasn't with her, much to the annoyance of other visitors. The Director finally got her to stop when it was pointed out that other disabled patrons couldn't park there when she was doing so, even without her daughter. No one begrudged her the space when her daughter was with her (except that she would usually leave the kid to be entertained by the receptionist while she was working, which was a separate issue).
2. I didn't really realize the issues faced by parents of disabled children until this particular incident. I had a student (getting a Master's) who was confined to a wheelchair. One Saturday, I went in to work and saw his mom pull up in a van and start unloading his chair. I hung out close to the front door, as I needed to chat with him. Mom kept throwing me concerned/irritated looks over her shoulder during this process. Once his chair was unloaded and he was under his own power that I yelled, "Hey, Fred*! How's it going? You coming in to work?" He yelled back, "Hey Dr. F! Good! Yeah, I have work to do." Me: "Good! I need to chat with you about work-related topic xyz."
At that point I looked over at Mom and was AMAZED at the look of sheer relief and gratitude she was throwing at me. The guy was doing a Master's and was still having issues with people talking to her instead of him. (I learned this later.)
*Not his real name.