I've been to Lake Tahoe sans baby in the Winter, but this trip would be the first I've seen the ground not covered by snow.
Karina was 9-months-old when we found ourselves in Lake Tahoe for our friend's wedding. We ended up doing an AirBnB in Incline Village with friends and it was the best decision. We were able to make her baby food, and set up lots of space in the living area for her to play. Plus, the neighborhood was really nice and we felt comfortable strolling her around for naps.
What to do:
The Beach at Incline Village - Actually, all the beaches are pretty incredible and picturesque. We took Karina out every day. This particular one had a bar with a view of the water right outside, so you can take in the fresh air and the scenery. See Travel Tips Section for what to pack for beach.
Get a sitter and charter a boat - We chartered a boat for 5 hours and it was an absolute blast. We highly recommend it, but don't take baby. The wedding organizer had recommended Sierra Sitters Lake Tahoe and we couldn't have been more pleased. Our sitter, Maddi, was incredible. We hired her ahead of time and she babysat twice. Once for our boat day, and then the next day for the wedding. She sent us texts letting us know how Karina was doing, and we felt very confident in her experience with babies.
Gamble - After the wedding, we ended up at Harrah's for the after-party. Half of us walked out with money. Half of us didn't. Regardless, a good time was had by all, and the bride won $700!
Car Situ - We also recommend renting a car. The Uber situation was a little shotty at times and the wait times would be over half an hour. Don't bother, and just do the rental.