When and what did you tell young children about moving OS?

[griffini]

We are moving to the US in August, my DD will be 4, and my DS 2. Am not sure when and what to tell them. We are going for three years and plan to return to when we are now? My DD 'knows' we are 'going to Boston' because she has heard us and others talk about it, but she doesn't know what this means in reality...

I would not tell them until shortly before the move. A couple of weeks maybe.

Telling them earlier will just unsettle them, they have no concept of time at the moment and will not be able to understand when it is.

I often use birthdays as a method of understanding time. 'First it is mama's birthday, then it is DD's birthday, then DS's birthday, and then we are moving'

Definitely not too soon, we told our dd we were leaving Bangkok in October, we weren't actually leaving the country until June. Stupidly I told her on an airplaine, when we arrived in Hanoi she decided that this was our country.
She really has little concept ot time even now and she is nearly 9.

We moved overseas when DS1 was 4 and DS2 was just under 2, they didn't bat an eye lid. DS 2 clearly to young to really understand, but from about 6 months before we moved I started to make them aware of the country we were going to and create some interest. I used books,computer, TV, noted things that came from there etc Then later would comment it would be nice to spend some time there see some of the things previously talked about. Then closer to the time how you get there hours to fly compared to school day. Slowly build it up before saying you are actually moving.
The leaving people behind thing is hard, but you know you are going back so not drastic.