Not sure if anyone else has experienced this, but last night at around 1 am, I woke up and looked at the Dexcom and noticed DD's BG was rising. Figuring it was due to the lasagna she had for dinner, I set a temp basal and tested and corrected. When I bolused, I could smell insulin, so I checked to make sure the luer lock connection was tight and realized that the cartridge tubing (the tubing that runs from the cartridge to the luer lock connector) had come detached at the luer lock connector. I had just replaced the cartridge and tubing on Tuesday and DD wears her pump in a SPIbelt so there is not a lot of stress or tension on the tubing. I opened a new cartridge from the same lot and tugged at it and it seemed tight in the connector, so it seems that we had a defective cartridge. When I called Tandem this morning to report it, they said that, while not common, they have received other reports of this happening. Luckily, I caught it early and was able to replace the cartridge and tubing right away. It's scary to think what may have happened if we didn't have CGM or didn't check on her last night.