Caitlin is a Welsh name as well as Irish and the Welsh Caitlins I have known have all pronounced it 'Kate-lin'.
Please don't try Kaitland, it will scar the poor mite for life. Imagine everyone she ever meets thinking she's the offspring of too real numpties...
(Baby name websites make stuff up btw - they've gone for 'pure' because that's the meaning of Catherine and Caitlin is the Welsh/Irish form of Catherine. This does NOT mean 'Kaitland' is a real name.)