The longest I've ever been without a pet has been about 1 year - in my entire life. Grew up with pets, have always had a pet of some kind around, so don't really know how it would be without one. My sister is very involved in showing, obedience etc. and breeds dogs so I'd have to say we're very pro pet LOL.
It can help, but make sure you go into it realizing that the pet will probably actually be YOUR pet in the end, no matter how much the kids want one and how much attention they pay to it, it usually ends up on the parent to do most of the care. IF you're looking at a dog, research any breed you look at, especially for temperament. Try get one that is very calm and patient. We got out last dog from the SPCA, and she can be hyper and barks a lot. This drives difficult child crazy. Would not pick one like her again, though she's part of the family now. Just a bit like having another difficult child around sometimes
This is not to say pound puppies can't be great. Before our current dog, we adopted an older cocker spaniel x from the pound, and she was a fantastic dog. We had her during some of difficult child's worst years, would put up with just about anything. Had her for 3 years and she developed a weird skin disease they couldn't fix that was raw and painful, so had to put her to sleep. I still tear up over her, she was a wonderful dog.
Maybe check this list of medium dogs. When you click on the breed it gives you the AKC description, temperament near the bottom usually.
http://www.animalhospitals-usa.com Some of the smaller "large breed" (perhaps a golden someone had mentioned) would fit too. If you see a dog you think might fit your family, research that breed. For example I've always liked the look of a Clumber Spaniel, which I think has a good laid-back temperament. However reading a breeders site, she was very honest about how much work a clumber puppy would take, as they LOVE to chew and can be destructive that way and take a lot of vigilance to make sure they don't destroy furniture and eat parts LOL. Not for me LOL.