Family 4 going to Italy December

I wouldn't go as far as Sicily for just 5 days. How do you plan to get there? And back to Rome? That's either going to be a lot of hours on the train (I've taken the night train, which was a miserable, sleepless experience) or two days when you have to get to and from airports.

Two nights in Florence will only give you one full day there. The partial arrival day is likely to be marred by jetlag and/or sleep deprivation for at least some of you. Do you not want to see places like Siena and Lucca? Three nights in Rome is also very short. But perhaps this is not your first trip to Italy?

Have you checked Amalfi Coast weather and temperatures in December? I don’t think it the time of year to visit it. Perhaps others on this Forum can give you an opinion of what it is like during December. It was very cold when we spent New Years in Rome a few years ago. We wore down coats, hats, scarves, gloves the whole time. Bbrrr.
Rome restaurants take reservations for New Years Eve dinners starting at 10pm. The city was packed with Italian visitors when we were there, grid locked in the piazzas. You need to be aware of these.
We spent four nights on beautiful Capri once in late September. The sea was too rough for the boats to go out around the island until our last day. I would not go all the way there just to see the Blue Grotto. If you do go to Capri, stay a few nights. As the poster above mentioned, you are giving much too little time to Rome and Florence. Your trip will be a blur.
Perhaps taking the time you had given to the Amalfi Coast combined with the five for Sicily, could add up to make a visit to Sicily more worthwhile.

So you have basically 2 weeks. I agree with previous comments that you'll be spending a whole lot of time in transit and your trip will be a blur if you do all this. Your boys are old enough to study up and help decide on priorities, but they may not realize how short the days are in December in Europe (hiking) and how rough seas can prevent boats from going out (Blue Grotto; ferries to & from Sicily).

You've chosen to concentrate on areas outside the cities. That makes sense, as it's pretty easy to return to Florence and Rome on future trips to see much more than your 2 and 3 nights will allow. Have you (parents) been to those cities before? Whether yes or no, you will want to decide as a family what you most want to see in each of these cities. There is a whole lot to choose from and with so little time you will have to plan carefully to avoid getting overwhelmed, or wasting your time on locations that aren't really very important to you.

Would you consider flying to Sicily and spending your whole 10 nights there before Rome? I haven't been there, but those who have comment about how it is a bigger island than you think and has lots to see and do.

I (mom) have been to Rome years ago. My family is interested in hiking and seeing sites like blue grotto, vineyards not really museums and we prefer quaint towns vs big cities. we liked the idea of Sicily because it’s warmer and less touristy

There is no need to make assumptions: Sicily has an area of 9,927 sq miles, the coast length is around 900 miles. It's a little bit smaller than Massachusetts.

Imho, You'd better pick only one place in Sicily and spend there all the 4 nights; a town not too far from the main airports and on a train/bus line to make a couple of day trips. Ideally you could fly directly from US to Sicily and return home from Rome (or from Pisa, to avoid backtracking).

Forget about visiting the blue grotto in December! Vineyards are basically muddy fields covered in snow around Xmas, hiking requires winter equipment and some experience.

Our plan was to pick one town in Sicily and one town on almafi coast 5 days each. I was trying to get recommendations for which town kn those areas would be best.

The towns on Amalfi coast will mostly be closed up for the winter- Positano, Amalfi, Ravello.
The only ferry service operating at that time of year is Naples-Capri-Sorrento, so even getting to and from any Amalfi coast town requires a car or driver or bus ( I would guess bus schedule is limited in December)
Capri will be mostly closed down other than local business.
Sorrento is probably your best bet, things will be open but still not much.
Check historical weather for the region. It will likely be chilly and rainy.

I doubt the Blue Grotto will be accessible at all in December. It's also the world's biggest tourist trap. Make sure your kids understand that it is likely not an option at all.

Vineyards won't be much to look at in December either.

Lots of info here:
https://www.sorrentoinsider.com
If you must visit the area I think Sorrento or Naples is your best bet.

I haven't yet been to Sicily but 5 days is probably OK- depending on where you stay and if you intend to base in 1 place with a few day trips. Where are you flying in to and out of?
Does seem like a long way to go and lots of travel time for such a short visit.

If I had to go to Sicily for only five days and didn't like large cities (which lets Palermo out), I'd choose Siracusa and stay in the medieval section of town, Ortygia. There are some nice Baroque villages (Ragusa, Noto, Modica, Scicli) not too far away. Do check to be sure there's public transportation running during the holiday period; it's not terribly frequent even in mid-summer (don't plan on any buses on Sunday). Siracusa itself has an archaeological park with a Greek theatre.

Train schedules: https://www.trenitalia.com/en.html

Bus schedules (see Routes 652-686): http://www.astsicilia.it/75701-2/

Pack carefully if you plan outdoor activities. There's considerable risk of rain in December, and the average low temperature is in the mid-40s F in Siracusa. Rome averages about 10 degrees colder at night and about 6 degrees colder at midday. Rome's at the same latitude as New York City, though fortunately it's not as cold in the winter.

Excellent advice from acraven, except I will add that although Rome is "not as cold in the winter" as New York City, many buildings don't have good central heating. At least this was true up to about 10 years ago; it may have changed since my good friend moved away from Rome. In any case, you'll want warm layers of undergarments and water-repellent outerwear.