Lisa was right on with temps being a possible problem. Another would be feeding to soon before lights out. Make sure especially with young dragons that they have at least 2 hours after eating to bask and heat up to start the digestion process. If not given enough time to digest before bed time, in the morning their stomachs could be a bit rotten. Food if able to sit in a dragons tummy without proper temps to digest will cause it to rot in the stomach =( not good. Make sure the last feeding is way before lights out, and give them a nice basking surface temp of at least 105 to properly digest before sleep. 105-110 is a nice surface temp reading right on the basking spot itself for proper digestion, 105-110 is not an air temp off the basking spot. If the air temps are 110 the basking surface depending on what you use could be well above 130 degrees. Ambient air temps of 110 and higher could be quite dangerous. So if you have a thermometer with a probe tape it right on the surface of where the dragon basks to get a decent surface belly temp reading, a temp gun is better for this but not many people have them yet. If you have a regular thermometer attach it to the basking spot to get a round about temp. Invest in one with a probe. Much, much better and more accurate for such applications. Temp guns for reading surface temps are the best thing though, and some can be bought at radio shack for around 20-30 bucks. A digital therm with an indoor outdoor probe can be bought for like 10-15 bucks at wal mart or a like store, and is well worth the money spent. Set the switch to outdoor and that will give you the probe reading on the basking spot. Good luck, hope these answers were the problem and nothing worse. Ohh also was it just crickets? Meal worms, and even wax worms can be quite hard for babies to digest. You would think wax worms being softer shelled would be easier, but this is not the case for babies.
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Mystical Dragons