Changing sleep/nap times can take time. It's a transition.
BUT... you need to keep to a schedule. You need to be the one to decide when your 13 month old needs to nap. A child can go on and make themselves stay up...but then they get "over-tired." And when a child is overtired, they can actually get more "hyper." Remember, nap/sleep is important for their development...and it recharges them and sleep is the time their brain and development occurs as well.
Some young toddlers will indeed fight a nap. But they really "should" nap. At this age they may actually go to 1 nap a day.
Typically, after waking in the morning... a morning nap at about 3 hours later is typical. Put him down at this time everyday (whether or not he "seems" tired)... have a routine about it. For my boy, who is 19 months now... I have ALWAYS kept to a routine and have a certain nap time. THUS, he is used to it, and he goes to nap without a problem. The key is that YOU need to take the lead, and keep to a routine. There have been certain periods where my boy didn't want to nap in the morning... but instead of then blowing off his naps... I just kept putting him in the crib at the usual time... let him wind down, and if he really resisted I'd take him out. BUT... BUT, I always kept to his regular nap time. And, he went back to napping at the same time as always. I've learned that at certain developmental leaps, he'd not want to nap. But again, I just kept to his same nap routines and times, and he went back to his napping regularity. He still takes 2 naps a day at his age for about 2 hours each... morning (about 9:30) and afternoon (about 2:30). And he goes to bed at night at 8:00, and wakes up in the morning about 6:30-7:00a.m. The same everyday.
He does get tired at his nap times, since he's so used to his routine. And I can tell when he is tired by observing him. The regularity is important for a child.
If you decide to sacrifice a nap, in order to take your eldest child to the park.. then you have to juggle the nap times of your youngest. That is the sacrifice.
For me, my 5 year old daughter "knows" that her brother naps at certain times in the morning...and after I pick her up from school. Thus, she does not demand that I take her out at these times. But after his nap, she knows that we will go to the park. Again, my eldest child, my girl, knows the routine as well, so she is adapted to it.
My boy, even though his sister is around after school, "knows" that he has to nap in the afternoons, and though he is playing with his sister... I will pick him up and start his nap routine... then put him down in the crib. And he falls asleep. I explain to him he can play with sister after he wakes up. He understands.
No matter what, I keep to the routine, EVERYDAY. This has been the key for me. And yes, this means that I have to juggle my own personal errands/appointments too, around my child's nap times. This has been my choice...but I am glad to do it because that provides my boy with his needed naps and regularity, and in the end it is better for him and me... and he is never fussy or tired.
Children thrive on routine and they "need" to know what to expect...then they will be less prone to "fighting" it. However, each child is different, with different personalities, and you have your own activities with your children.
However, just wanted to share what I do with both my kids. The routine I have with them keeps me sane, and keeps them on an even keel too. Sure, there will always be times where they don't want to nap... and so reducing it down to 1 nap a day is up to you. But try different things. See what works for you. But at 13 months... a nap is still important. They need that at this age. Good luck you will get all kinds of suggestions and experience here.
~Susan
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