Ah 19 months - same as mine and boy are we having problems!
I would definitely move her bedtime much earlier - this is one of the ways of helping them sleep longer - you should find lots of threads on here about dealing with early risings. I would give her tea at 5pm, heading for bath, story and bedtime by 6.30 or even earlier.
I would also gradually move her naptime later by maybe 15 minutes a day (I think I need to do this with mine - she woke at 4.30 this morning and never went back! Absolutely pooped by 9am, but I managed to stretch her out till 10.30am!). That way hopefully you will even out the distances between sleeps. I do think that the early nap just encourages my daughter to wake up earlier in the morning, and makes a horribly long gap between nap and bedtime.
Try an earlier bedtime, maybe even 6pm - you'd be surprised how much difference it can make, but check out the threads on here for more advice too...
Hope this helps - I'm no expert - with an 11 week old and the 19month old I have really got my work cut out!