I find it hard to believe you have received no answers to this but then this is the first I've seen your question and I check in a couple of times a day.
OK, if you've never been here before, Cary is a great place to live but don't rule out Raleigh, Apex, or Holly Springs. All are close to Cary and great places to look. They are also part of the Wake County Schools system and this may enlarge your search. You can go into the school system website at www.wcpss.net and reeaach all the schools. Since you are moving, don't be afraid to call the county schools office number that is listed on the site. They are very used to people moving into the area and maybe able to help you place your children even if the school is capped.
For rentals, I could check the local MLS for you to see if I could find dog friendly homes. If not, I know a couple of excellent property managers who could help you as well. My wife and I are foster parents for the local animal shelter so I always welcome newcomers who put their dogs in consideration. Please feel free to call me or email me . My contact information can be found under my picture or via my website listed below.
I hope this reaches you in time...Good Luck!!! Call me!!