5:14 PM PT -- Travis' medical emergency is starting to sound more serious ... because his daughter is asking for prayers.
Alabama Barker took to social media after her dad was hospitalized and asked folks to send prayers to Travis.
Unfortunately, the "in sickness" part of Kourtney Kardashian and Travis Barker's vows is already coming into play ... the drummer was just hospitalized, with his new wife by his side.
Barker and Kourtney first showed up at West Hills hospital Tuesday morning for a health issue Travis was experiencing. Apparently, the medical crew at West Hills felt Travis needed additional care, because he was then taken by ambulance to Cedars-Sinai Medical Center.