Riddle - Born to prosperity and comfort, his muggle parents either kept him from getting the invitation to Hogwarts or it just never came. He almost married another muggle named Cecilia, but before they could elope Merope dragged him off to her magical world. And well, it was amazing to the eyes of a young man who thought he had everything. He fell in love with this woman who was his opposite and yet completed him, and they started a family, he catching up on magic and eventually deciding to become a Professor and teach it himself. Currently 53 or 63, depending on if you count the years he was alive or dead.
Merope - Riddle's wife who stole him away from his girlfriend after graduating from Hogwarts. Although she was obsessed with him in youth, he never cared for her because of her looks and being of a lower class. But after they got married and their children began growing up, maturity set in and her love turned to romance and fantasy. Merope specialized in potions and used them to keep her youth and beauty in an effort to keep her husband's interest, a bad habit their children learned from her. She died only a few years after her husband, at the young age of 40, and her soul sought his across the void he had wandered. There they found their love still strong, but Riddle was called back. He doesn't remember much, but knows he found peace and she found him, and they were to be born again there on that new world.
Tom - 15 years? Their youngest son, he's currently in his 4th year at Hogwarts. He was only 5 when his father died, so Riddle doesn't know him very well, but expects that he did him proud.
Darla - 22 years. Their younger daughter, she has just gotten married and had their first child; the toddler gets into a lot of trouble.
Byron - 25 years. Riddle's oldest son, Byron shared his mother's flare for the dramatic, but never seemed to really care about anything but wine and women. He has two children, a son named Perrigan, who seems more interested in muggle technology than magic, and generally locks himself in his room to use computers all day. And a daughter Abagail, who is rebellious, zany, and has a good heart.
Lola - 30 years. Riddle's oldest daughter, has two beautiful, quiet daughters and a young boy who is curious about everything and is always chasing his sister Terra's adopted pets.