Usually people say that its better to house leos with other leos only and personally I plan to be a breeder so I keep leos with leos to. But in reality, it depends on your leo wether he or she decides to cope with it or not. I have a friend that breeds Bearded Dragons, he houses his young Dragons with his Male Leopard Gecko.
There has yet to be any fighting or anything between the lizards. The leo notices the dragons but seems to care less if there in his territory or not. (I should take a picture of this), its cool to see 2 very diffrent lizards live in the same tank.
And according to my friend, he hasnt ran into a baby dragon that wants to pick a fight with the leo, so its all good.
Once again, be careful, it depends on the leo. Especially if you have a so called "hot male"(soposely when you incubate a egg to high, you get something that is called a Hot Egg, which ends up being a very Aggressive offspring, Hulk Leo or something).
And just to end it with something good, USUALLY, Geckos only fight other geckos that Raise there tail that state there male. When 2 males realize this, they will go at it.
Now im not sure if a Dragon does that, but thats probably when my friends leo hasnt picked a fight with one of the dragons, no tail raising?
Good Luck
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Normal - Male - Ninja
High Yellow - Female - Ninjete