Barging in to say I love the idea about a nightlight with a timer, so I'm off to the shops to get myself one
I'd love to be a fly on the wall but I'm sure our DS calls out "time to hop up now" the minute he opens his eyes!
DS1 has always been an early riser (6.30 is a sleep-in at our house
) but DS2 is like your LO and loves his sleep. We are having 2 -1 nap transition earlier wakings, but for the most part he's woken at 7 a.m. or later. So my sympathies to you!
I suppose you've tried all the tricks to blocking out the sun coming through her window in the morning?