This thread gives me flashbacks.
I had this in my old flat. The terraced houses across the road had gardens backing onto our complex. In the one house, there was a girl. For three years she would shriek scream, really high-pitched long undulating ones, all day every day. It was enough to make you go cross-eyed. It was so bad it used to sometimes, and quite literally, upset my stomach. Don't know if anyone will get it but real sphincter puckering sound. The screaming used to set their next door neighbour's dog off, big mastiff looking beast, so it would start barking and clamouring to get over the wall. The parents never intervened. Quite how that dog never got to that child I will never know, nor how the parents couldn't see the danger. The walls were not even that high as it's paws and head were atop that wall and the wall was quite flimsy. If that dog had been of a slightly different weight, that child may well have been in serious trouble. A relative visited me with her newborn the once and exclaimed, "WTF, my milk just curdled in my breasts".
I moved. Blissful silence. Then lockdown one came along and two families with lots of kids started spending their days on rugs outside the window of my new home on a patch of public grass. They treated it like their own private park. Screaming, shrieking, shouting, throwing stuff at the walls and windows of surrounding properties and at cars. All the while the mums sat there on their thick rugs with big pillows loudly gabbing away at warp speed and never getting up to deal with their kids. It was like I had died and gone to hell. Every lockdown they did this, seven days a week, from 9am to 7pm or later. It made my health worse due to the stress of the constant noise and sudden loud outbursts of high pitch screeching. Couldn't block it out by shutting windows and doors. Couldn't leave the house as shielding. Couldn't move as lockdown and no money to do it again so soon. I'd spot them waddling over and my heart would sink. Earplugs, nor industrial ear defenders didn't even block it out.
OP you have my sympathy.
Also, just because it's noise from a child and/or ND person, doesn't make that noise any more pleasant nor easier to live with. Unfortunately, a kind or tolerant heart won't protect your ears nor your nerves.