The purpose of this study is to learn more about changes in glucose levels in hospitalized infants with intestinal failure receiving parenteral nutrition or PN (nutrients delivered intravenously), as they transition from continuous PN (given 24 hours a day) to cycled PN (given less than 24 hours a day). There is an increased risk of glucose abnormalities with cycled PN, which can be harmful to infant growth and brain health. Continuous glucose monitors (CGM) will be used to measure interstitial glucose levels (in the tissue under the skin), which are similar to blood glucose levels. CGM is a small, minimally-invasive sensor worn on the thigh, which gives a glucose measurement every 5 minutes, and can help us understand changes in blood sugar levels without having to do a blood draw or fingerstick. CGM will be used during PN cycling for up to 30 days or until hospital discharge. If target GIR cycled PN is not reached following 3 sensor periods (up to 10 days per sensor), the parent/guardian will be approached to accept or decline participation in an optional extension phase. In the extension phase, the primary study will be repeated and CGM monitoring will continue until target GIR cycled PN is reached, up to an additional 3 sensor placements. CGM data will be hidden from the clinical team, there will be no change to routine clinical care. CGM may provide false low glucose readings when the tissue around the sensor is compressed (compression lows), such as when laying on the sensor during sleep. We will generate data during the study to help identify and filter the final dataset to remove likely compression lows. This study may help us understand how cycled PN affects glucose levels in infants with intestinal failure, which may help other children treated with cycled PN in the future.