questions for 863211

Dear 863211,

I have questions for you.

My daughter and I have green card. We left to China on 1/18/12 and planed to return to US in Feburary this year. But my daughter (12 years old) broke her leg (bon fracture) on 2/18. She is still in the process for healing, therefor, our return date might be July 16  or August. I don't know if it would be a problem. What problems would be?  If we need a letter from her doctor about her medical condition for the US customs afficial, what do we need to illustrate in the letter, do you have sample letter?

Thanks very much,

Looking forward to hearing from you ASAP.