I'm moving to the UK in 2 weeks, with my 3 children. My 13 and 10 year old girls and my 2 year old son who is a dual citizen. I just read a post about someone who is having a really hard time adapting and can't sleep.
To be fair, the person who is having a really hard time adapting has only been in the UK for about a week (got their visa May 1st, wrote the overwhelmed post on May 4th!), moved here alone on a work visa and is in the centre of busy London. Plus they are fairly young and they've lived with their parents their whole life... it's their first time living anywhere on their own, as well as their first time living anywhere but their home town, let alone 6,000 miles away on a new continent!
They've just gone from a comfortable existence living with parents to navigating a whole new country, new continent and one of the busiest cities in the world all on their own. Not only do they have to worry about how to live alone and do everything for themselves (find somewhere to live, set up banking, utility bills, navigate the city etc.), but they have to learn how to do it in a new country where everything is unfamiliar, as well as deal with a new job all at the same time.
I'm not surprised they are feeling overwhelmed by it all!
A new school, new friends, new everything and one is a teen and the other a tween. They've been excited to move since we discussed it last year but I'm guessing by the sound of things, that may not be the case once we're settled and there.
To be honest, if I had moved to the US when I was their age, it would have been the most amazing experience of my life (I visited family in the US when I was 12 and I fell in love with it - I cried for weeks after I went home because I wanted to live in America)
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Remember, you and your family have had months to prepare for this, and the kids are young and adaptable, and they are moving with you as a family unit, not completely alone - they will have support from you and your husband to help them adjust and for you all to get through it together.
Of course, they may find there are things they don't like or aren't what they are used to and they might discover that it's not what they thought it would be, but that's normal. I really don't think you can compare what the other poster is going through to your kids' situation... it's completely different.