Long answer to short Q... but I think you'll like it:
I have ringlet curly hair. It starts locking up (when it's curly) in less than 24 hours. 1 sleep, or 1 active afternoon. I have a several page list of instructions on how I deal with it to KEEP it all Shirley Temple. Most of the time I blow it out straight for the sheer convienece of it. Yes. Even when i had shoulder blade length and longer hair and blowing it out takes 2 hours, it's FAR less hassle than dealing with the curls. (Most of the time I keep my hair fairly short so that it only takes 30 minutes). YES, they're beautiful when I take the time to deal with them. NO, I have too many other things in my life to spend the time having gorgeous curls.
And if you DON'T spend the time.... they lock up. If you DO spend the time, they lock up in 24 hours.
So when I was in middle school I got really into surfing. The locks happened on accident as a byproduct of half living on the beach with friends one summer (they lived on the beach, and half the time was in the house, the other half we just camped and waited for the tides in the morning).
OMG... LOVE dreadlocks.
Because of the saltwater they locked "straight & small" (about finger thickness). When they first happened, I was horrified and embarassed, BUT my friends parents didn't make disgusted faces and get that gut clenching tone about "MATS in your hair". Instead, they got all delighted about how fast they formed, and showed me how to roll them. BLISSFUL summer of not hating my hair for the first time i my life.
A week of surfing and rolling them absently during fire time and I had foot long locks. They were beautiful.
Of course, my mum combed them out in the fall (with the "Ugh! MATS in your hair!!!" comment). It took 3 excrutiatingly painful days to comb them out. She did it, me sitting in front of her.
Next summer, I locked them up again. And the next fall, she combed them out again.
The ONLY thing I didn't like about them is that they're a bit scratchy. Clean, smelled good, looked GORGEOUS... just a bit scratchy.
If your son likes them, GO for them. Let him be happy with his hair. Let him feel good about himself, and feel good about yourselves for not putting him through the torture of trying to maintain Shirley Temple hair. Maintaining those curls is PAINFUL. It's time consuming (a waste of time in my humble opinion).
It's not neglect... it's a style. A "black" style, which some people will NEVER like.
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Oh... and Z is going to look GORGEOUS with them, when they're done. He has exactly my kind of hair (from the photos), just a different color, and his face shape totally supports them. Drop dead gorgeous. And because he has "my" kind of hair... you'll never have to worry about "dull", because you won't need wax. Most white people have straight hair, and it won't lock without wax. The four tricks I can offer is
1) to make them small to begin with (giant thick locks look strange on small heads, and they get wider the longer you have them... go for about pencil thickness to begin with, as opposed to hotdog thickness
2) to pick the section, comb it straight (the salt water did that for me, and the few times I've decided to lock back up as an adult, I just use saltwater in a bowl to get the same effect), and make them as "long" as possible (they always shrink) so that they don't ball up (super easy to have happen with dry curls)
3) douse in salt water to help. ((Straight hair gets all brittle when wet, curly doesn't))
4) Make sure they "stand up" when you're doing the top / have him lean his head over to the side when doing the sides, etc. They lay down from the weight (eventually, depending on length), but doing them "out" keeps them from "plastering" to his head, and will make them so they can "swing freely" as they grow.
Have fun!!!! I'm SO jealous of your son for not starting off every day for the next 10 years crying because it hurts to deal with his curls, like I did until middle school!!!