We were at the MK last Easter. Easter coincided with our Spring Break for our school district. Thankfully, this year it didn't. It was extremely crowded that Sunday at the MK, the most crowded I have ever seen. My best advice is to take advantage of any EMH that might be offered on that day. Focus on the rides/attractions that are most imporant to you all. Expect to wait, have an early start, don't become to stressed out!
Remember to have fun, possibly it won't be as bad as last year, because Easter seems alot later this year, and won't be as crowded.