Movie about 2 siblings (i think) looking for a new home

I watched a movie as a child, probably a few dozen times, about 2 kids who I believe are siblings and their house burns and they are looking for a new home. All I remember are a few scenes but I’m not sure if they are from the same movie: they get to an old lady whose house is very cold since she is scared to turn on heating because she believes the pipes will explode and they do explode when the kids leave. And the other scene is where a man leaves them in a car on train tracks for an oncoming train to hit them.

I know there isn’t a lot of details and there’s a big chance I mixed few movies together but anything would help, I appreciate your time!