What to share with my 11yo

I would just tell the basics.  Surgery for stomach and you will need to stay X nights and will be on a special diet and explain that to her.  I would also answer any questions asked.  I would not go thru the whole process at this time unless asked.  As questions come up answer with honesty but she may not need to hear it all now.

I told my 6 year old daughter that I was having stomach surgery to fix a problem that would make me feel better.  I will tell her more in the future, but she gets overwhelmed easily so we decided to give her just the basics for now. My 10 year daughter thrives on facts and needed all the information.  She knew I was fat and unhealthy and that this surgery would help me lose weight, feel better, and have a healthier life.  Every child is different.  Don't lie, but give them only the information that they need.  Stay positive when telling her and  she will be fine.  Good luck =)

Thank you everyone! Great advice. I wasn't planning on lying but we chatted and I let her know she could ask any questions anytime.  Funny thing is I. said that I'd be  wearing smaller clothes next year like she does and she said, you are small to me and you give the best hugs just like you are! 

I agree that the truth is usually the better way to go. My daughter was 12 and just turned 13 and I am only 5 weeks out. I had severe diabetes and she know how sick I was so she was happy I was going to get healthier. My daughter battles with weight also because of picking up on my bad habits! Since surgery I have been able to inspire her and we look at labels and excercise together :-)

I think everyone has given you really great advice!  I'd like to add that if my mom had lost a ton of weight rapidly when I was 11, I would have freaked out and assumed she had cancer and was dying.  So.. I'd have liked to know what was going on :D