Olive didn't sleep through the night until 16 months, but since then she's been a great sleeper (she's almost 20 months now). She sleeps over 12 hours at night (but can sleep over 14 if we let her), and takes a 2 1/2 hour+ nap.
Charlie's sleep is in transition since he will drop a nap in the coming months and the bedtime battles could be improved.
But... I would definitely improve their eating if given the choice. Both of them are going through a super picky spell right now. Maybe it's the heat?