Prague to Budapest

Bratislava?

I was just looking at that. Is it worthwhile to visit?

Bratislava or Brno are on your way and both are worth visit. It is nice to break that long train trip.

Ok I will research both. Would 1 night be enough for either place or would 2 better?

Brno is a wonderful city and a complete contrast to Prague, a friend of mine lived there till very recently so I visited a few times ,lots to keep you busy for several days, you being there in October you could head out to the Dam area for a late afternoon walk ,stunning area and easy to get to by tram from the city centre.
If travelling by train check that the train station is back in operation , been closed for a while for refurbishment and not sure if it has re-opened.

If you have only one night what can you do. Two is always better. Unclegus is right that Main Train Station in Brno was closed because of reconstruction of an overpass. But train still stops in Brno - twice: in Zidenice and Brno dolni nadrazi. If the Main station is now open it would be more convenient. There is a lot of public transportation right in front of the station.

That's sounds great. I will look into the train situation. I've left final planning this trip a bit last minute as we were going to do Croatia. Is there a specific train line or can I just google trains "to and from"?

I think we could do two nights. Take the train from Prague on Sunday to Brno and off to Budapest Tuesday morning.

I'd just use Ceske Drahy, the official Czech Railway site. The Railjet trains have good on-board services.
https://www.cd.cz/en/

Perfect! Thank you.

My choice would be Brno if you do make a stop.

I agree with the recommendation of Brno - take time to see the cathedral!