I know that this response may be way to late, but it may help you for future refrence for your other leopard. First if your leopard is on anything, I repeat anything other than Paper towels, newspaper, slate or tile, get them off of it! NOW! not kidding, at this age they are A: not good at hunting, B: Have a tiny tiny digestive tract, and C: will eat foreign objects ie sand to quell their constant hunger. So if you have already done the substrate thing, and the geck is still kickin, seperate them permanently! A sick or impacted gecko has no chance of getting enough to eat with a healthy companion like you have, Next, if you need to know that the limping thing probably from lack of calcium, because the gecko can't get it from food items, so thats why it's bones aren't able to carry the weight of it's body. If its impacted it will need a vet attention, they will either try and scoop out the impaction through his/her butt, and then put it on an appetite stimulant. The gecko needs to be soaked, in a very shallow cup/bowl of warm water, to help ease the digestive tract and hydrate it. If you want to try and feed it make a slurry mix (search forums gecko for exact recipe) of crushed crickets and meat type baby food, mine liked chicken not turkey. The third possibility is that it hasa an illness, like coccidia or crypto, in this case for sure you must seperate the two, take it to a vet and have a stool sample one that is fresh or one that is old, it does matter, but take whatever you have and have them do a fecal. I have given you all the things that I did with my Baby Gaza, she would have made it if I had done this earlier than I did. Best of Luck to you and your geckos.