I actually really like Kayleigh. ;) I don't think there are many babies named Kayleigh nowadays. Which is probably why the name seems really fresh to me personally...
According to behindthename (no idea how reliable that website is, btw):
"Variant of KAYLEE. This is also a common Anglicized form of the Gaelic word ceilidh, a traditional social gathering and dance."
According to this the OP's idea of naming the DD Ceilidh may not be that weird? Idk, I'm not Scottish...