I've got a 15 month old DS and he is refusing to sleep in the morning.
He's routinely done a morning and an afternoon nap each day - usually for 45-60 minutes.
He's now refusing to sleep in the morning but is super cranky and still only sleeps for 45-60 in the afternoon. He's then a nightmare in the evening.
He sleeps consistently through the night, so it's not all bad.
The minimal sleeping in the day just means he's tired and whiney all day.