Classical … with a toddler?

I think you will find that Vienna is a city for older people (elegant, grey-haired people with fur coats and poodles). I couldn't find any musical events suited to bringing small people under 6. I think a church rather than a concert hall or opera might be the way to go (a more forgiving crowd), and easier to make your escape if bub is uncooperative.

In spite of this there is a bit for families in Vienna - the Zoom Kindermuseum is good - we spent two summers on sabbatical in Vienna when our daughter was small and took her here: https://www.kindermuseum.at/jart/prj3/zoom/main.jart?j-j-url=/en . You will also want to visit the Christmas markets at the Rathaus, where there is a lot to entertain little ones (rides, food, nativity scenes / fairy tale scenes). There may be some music there, not sure. We found the famous cafés unfriendly to our daughter who was 4 at the time, so rethink that perhaps. There is also a great aquarium in a former flak tower, highly recommended, and I am sure that would be open at that time of year. And there is the Ring Tram - even trams can be fun for little people.

There are other things for families in the summer like the Prater, and there are things that you would want to take your little one to such as the Lippizaner stallions, but alas, there are age limits there too. So in all it's difficult in the winter, but I hope i have given you a few ideas.

Lavandula

And there is the Ring Tram -

The so called Ring Tram, especially operated for tourists, does not exist anymore. But you can ride a full circle around the Ring boulevard with regular trams and one change.

Sorry to say, but with a toddler of that age you won't be able to attend any cultural event (opera, classical music).

You will find all activities for toddlers here:
https://www.wienxtra.at/kinderaktiv/0-3/
The pages are in German, but using an automatic translator you will be able to understand.

As stated above, Vienna likes small children quiet and often out of sight. I know - I raised two children here. Screaming children get the looks, I can tell you. Definitely only take an 18 month old to a show/performance specifically for small children or else everyone's eyes will be daggers. Restaurants can also be tricky - lots of looks if the child isn't quiet. That said, if you know where to go and what to do, Vienna can be child friendly - children just aren't really integrated into everyday activities here.

For the Christmas Markets, definitely go to the market at Karlsplatz where there is a huge play area for small children. The area includes small animals as well. This market also has the best crafts of any market in the city - it is my favorite with or without children. The market at Schonbrunn this year will have a new light show in the garden, which sounds fun. The small but very cute market at the Vienna Transportation Museum (Remise) features a craft area and is very family friendly. Finally, I really like the Altes AKH market for small ones (this one also has the best food) - the atmosphere is open and family oriented with puppet and magic shows on the weekend. I definitely would not advise going to the Christmas Market at the Rathaus with a toddler - it is too crowded and chaotic, making it not very enjoyable these days.

For concerts, I looked online and found these ideas:

Hase Hoppla und der Weihnachtsbaum (Bunny Hoppla and the Christmas Tree) https://www.lilarum.at/hasehoppla.html - but only for ages 3+. I am including this in case anyone with older children read this post.

Puppet Theater https://www.maerchenbuehne.at/spielplan.html - but again only for ages 2+ for most productions.

Haus Der Musik Concerts https://www.hdm.at/konzerte/?konzert-kategorie:8/ - there are some children's concerts for very small children.

As mentioned, Zoom Children's Museum has programs for toddlers. We also really like to take our little ones to the Technical Museum and the Haus Des Meeres aquarium. I do not recommend the Natural History Museum for small children as the large stuffed animals can be scary.

Restaurants can also be tricky - lots of looks if the child isn't quiet. That said, if you know where to go and what to do, Vienna can be child friendly - children just aren't really integrated into everyday activities here.

We even reverted to Maredo as a 'restaurant' that is child friendly. Well it is, it just might not please Mum and Dad so much. We didn't have such a difficult time with restaurants as we usually self-cater, but we managed restaurants that we did go to quite well. And if you are feeling inhibited, many restaurants deliver ...

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Oh, and Austria has Kinderhotels out in the regions, and trains often have a family carriage so that kids will be entertained (think large space with generous play area and colourful decor). It's not all bad for children, but there are adult zones and kid zones and never the twain shall meet...

Lavandula