DD is 12.5mths and until very recently has always needed a nap approx 2-3hrs after 1st wakening in the morning. She can be a very early riser, so sometimes eg we'll have a 5.30 start, she's exhausted by 8am and back up from her 1st nap by 9am! It's quite convenient tbh as it means that she is then up for about 4hrs and you have a full morning to get stuff done etc.
However she's started not falling asleep at morning nap time (she normally gets taken out in the pram with whoever is walking the dog and goes out like a light)so I presume she is just getting ready to drop this nap. But she is sooooooooooo tired and grumpy all morning! Today she woke up at 7am which is pretty late for her, no nap, so went on out and met a friend etc - she was a nightmare, so tired, wasn't her normal cheery chatty self at all. She went for a massive 2 hour sleep at midday which was a bonus, but the morning was a disaster! Is this just going to be a phase until she gets a bit more "stamina", for want of a better word?