I have two Leo geckos.... Leo, the fat one who never eats in the fall, and Bob, who swallows every mealworm I give him and still does not get bigger. Bob has a crusty feces of some kind forming, and I have pointed this out to my parents but they say it's nothing.
Are your parents herp vets? Haven't heard that they are, so accepting their opinion that nothing is wrong with your leo seems like a problem. If you are truly concerned enough to get to the bottom of these health issues, you will need to have an experienced herp vet examine Bob. Bob may have intestinal parasites that are preventing him from growing. It may also have something to do with these "crusty feces" you mentioned. If your parents won't pay for a vet visit or won't take you to the appointment that's a really serious concern to face before getting an even more delicate animal. The reality is, the chance that you will need vet care for a new 1 month old cham (even I am hesitant to buy one that young especially of a species I haven't kept before!) regardless of species is pretty high. It would be high for many keepers of any age, not just you.
Leo sleeps a lot. He's really lazy. On top of this, Leo seems to be unresponsive to many things, or maybe he just doesn't care. Let's see what else..... Oh yeah. Leo's right eye is always half shut, the other one is fine though. I always tell my parents something seems wrong, but as I always say that they believe I am just overly sensitive towards them.
Again, if your parents are not herp vets who can actually diagnose and treat gecko health problems I think you need a vet's opinion. Sounds like Leo has some issues too.
I'll have to stress to them that this cannot happen with the chameleon.
If they dismiss the probable health problems your leos may have or are not willing to get them to a vet when something isn't right, this doesn't bode well for a cham. Are the leos less entitled to decent vet care than a cham? Think about that. All your animals deserve the same level of care regardless how rare or expensive they happen to be.