I wrote you a long post and, poof! It disappeared.
Has your child had a nasoendoscopy done? It's important that this is done before ANY surgery. If your child has any nasal speech, and expecially a short soft palate, you don't want to remove the adenoids. They are a roof to the soft palate and removing them makes the palate have to work a lot harder to touch the roof.
I went through this with my son. His ENT keep pushing me to take out his adenoids because he had sinus infections. He wouldn't do any diagnostic testing, and I simply wouldn't let him take out the adenoids without looking at the entire structure. I got a second opinion and did a nasoendoscopy, and turns out the the adenoids were small and uninvolved and DID NOT need to be removed. I'm so glad I didn't do this.
Do your research. Read about deep nasopharnyx, which taking adenoids out can cause if there are certain structural issues. If your child has ANY nasality in his voice, he can end up with hyper or hypo nasality that cannot be fixed from taking away the roof of the palate. If your child has an undiagnosed submucous cleft palate, taking away the adenoids will wreak havoc on her speech too.
Insist on a nasal endoscopy before you allow the adenoids to be removed. It's REALLY important.