Fix gap in stomach muscles?

[Tigpuppy]

From my twin pregnacy over 3 years ago I was left with a fairly wide gap in the muscles of my stomach. When I used to tighten them, I could fit my fist into the gap. Now when I tighten them I can still fit 2 fingers into the gap. I've been told that it's dangerous for me to do sit ups or crunches because it could cause my intestines to push out thru the gap in the muscles.

I know many moms of multiples have had to have surgery to correct this, but I'd rather try more natural methods first. Does anyone know of exercises that will shrink this gap and tone the muscles in this area?

Thanks!