First, some advice. All of my babies have had slightly different preferences for how to be dressed at night. Some liked socks, some hated socks. Some liked to be dressed warmer and some liked fewer clothes on them. You will have to experiment and pay attention to how well your child does/does not sleep with certain clothing. You will want to experiment even down to the fabric of the items you are wearing. A micro-fleece swaddle blanket was the favorite of one of my children, while for another it was too hot for her and she preferred the jersey knit.
A baby or young toddler will not sleep and keep blankets on; they move around far too much. You also want to be wary of blankets in the crib with babies before they are old enough to move them away from the face on their own while sleeping.
Because of this, I do layers. My idea is I put the child in what I consider to be the pajamas and then put something over it like a wearable blanket. This might be a swaddle blanket, a sleep sack, or it might be footed pajamas.
A typical way I dress up my children when they are young are:
This is pretty consistently the first layer I use for any sleep time of year. This is the basic onesie.
I then add socks. I had one child who hated socks, but the other three all have/do sleep with socks on their feet. We do socks year round. Cold feet are a very common reason for waking early, so I think it is wise to start with socks and then remove them if you think the child does not like socks for sleeping.
Layer Three: Extra Warmth
The next layer is extra warmth. If it is cold weather outside and the baby is 6-9 months or younger, I do a cotton footed pajamas like this Zip up sleep and play pictured at the right. If the child is older than 9 months but likes to be extra warm, I will do this layer, also.
For the child who is 9-12 months or older, I will do some basic cotton pants if extra warmth is needed.
If it is warm outside and the nights are warm, I do not add the extra warmth layer. This layer is skipped.
Layer Four: The "Blanket"
For a baby who is still swaddled, the next layer is a swaddle blanket. That often completes the ensemble. If baby needs more or less warmth, try changing the fabric of the swaddle blanket you are using.
For the baby who is not still swaddled, there are a couple of options for what to do next. From the time baby is done being swaddled until somewhere around 9ish months, I typically do a sleep sack.
At some point, the baby will start rolling around more and want to be more mobile. Somewhere around 9-12 months, we move from the sleep sack and into the fleece footed pajamas. We stay in this until the child no longer needs layer four. This can be for reasons varying from it is too warm at night for the layer to the child has grown old enough to keep blankets on while sleeping.
Layer Five: The Extra (optional)
When Brinley was a baby, Merino sent this sleep sack for me to review and I absolutely fell in love (you can see her pictured in it in the first picture on this post). I totally wanted one for myself. This is the Merino Kids Baby Sleep Bag. The one I linked to is the winter weight one and they have a normal weight one. Merino wool is amazing because it is itch free and allergy safe. It keeps the body at the perfect temperature--not too cold and not too hot. The room temperature range to use it in is ten degrees (winter weight is about 59-68 degrees), so no matter what the temperature is in that range, your child will be at the right temperature.
This product is awesome because it takes so much guess work out of it. You will not regret owning this. They also have sizes for 2-4 years old if your older toddlers and young preschoolers will sleep in a sleep sack.
When Brinley was a baby, she was swaddled with this over it. Then we did the sleep sack with this over it (she likes to be warm).
As a side note, there are many other products made of Merino wool, so you can get onsies, shirts, socks, etc.
Another important step is figuring out what room temperature is best for your child to sleep in. Most sleep experts say to sleep in a room from 64-72 degrees for optimal sleep. A tricky thing is keeping your house warm enough for the baby who sleeps with no blankets and yet cool enough for those sleeping under a pile of blankets (or in the summer, cool enough for the older people while warm enough for the young ones who can't pull blankets off and on as needed).
Ever since Brayden was about 6 months old, our babies have slept with the space heater you see above. We let our house come down to about 63/64 degrees and night and keep the baby room at 70 with this heater. For a while, we kept it with the older children as well, but we took them out of all of the rooms except Brinley's last winter. The other children are old enough to sleep with blankets and a space heater can add quite a bit to your electric bill. We try to only use it when the door will be shut so it can minimize the need for it to turn on.
You can definitely sleep with your house warmer at night rather than use a space heater for one room. By about age three, most children can sleep with blankets at night and keep them on.
As you figure out what is best for your baby, remember to experiment with the different layers and see how your baby likes it. Some rooms are warmer than other rooms, some houses are warmer than others, and some climates are warmer than others.
How do you dress your young ones for sleep?