yes, I agree - it's very possible. My daughter is pregnant with our first grandchild and she's 25. My son is 23 and is just getting engaged. I have a feeling they won't wait real long. But the other side of that equation is where they end up living. My daughter is less than an hour away, but my son will be moving between 2-5 hrs away, depending on which grad school he chooses.
I totally agree with the OP: there really is nothing better than having children around. It's been a very difficult (heart-wrenching) couple of years as my children have begun leaving the nest. I still have an 11yr old, so I still have time... but it's not the same as when my house was filled with school-aged and/or little kids. I've been very nostalgic for those days.