A bright and educated boy passionate about math, chess, and swimming. Always restrained and reasonable, but a little unconfident. He spends all his free time reading. At his young age he already possesses a decent library, giving preference to scientific literature rather than fictional, which is not surprising, because you have before you a future scientist and, perhaps, a Nobel laureate!

Unlike Danya, Dina is very talkative, lively and active, sometimes even rushing and impatient. She fantasies and plays around a lot but she’s always ready to take care of her brothers and come to help. Dina has an artistic spirit, she really likes to draw pictures! In Dina’s room there is already a gallery of her works, and she awaits an invitation to a biennale of modern art.

In everyday life little Yakov is an energetic and curious child. Although he has not yet learned to speak, he has absolutely no problem with expressing himself and always achieves his goals — be it an older sister’s toy or a cherished candy basket. But within the Secret Room, Yasha turns into a superhero — the Rabbiman! Rabbiman wears a traditional Jewish hat and a talit, and has the ability to transform into a plane!!! And so it’s only with Yasha’s mischievous and fearless nature and his sharp wit that the kids can handle all the trials of the Secret Room!

He is a programmer who spends a lot of time at work, but always gets home just in time to put the kids to bed. The kids' favorite pastime is reading books with Dad before bed. On his days off Dad plays with children and makes up wonderful new games for them. It’s never boring with Dad around!

She is a school teacher of Jewish history. Mom regularly takes Danya home from school and picks up Dina from kindergarten. The kids are sure that, although Mom is a little strict, she’s the best in the world, the sweetest and the most caring. When she goes to work or tends to some other business, the children stay with their father or with their grandparents.

Grandpa effortlessly finds a common ground with the children, better than all the other adults, as he has preserved in himself an unlimited childish imagination and the ability to make up stories. He likes to spend time with his grandchildren and daydream; he often has his head in the clouds. But because of this he successfully writes children’s books and may very well be aware of the existence of the Secret Room!

Grandma loves her grandchildren very much, so she often visits them and brings them gifts. In addition, she is always ready to share some family stories, of which she remembers a great variety. Grandma Rosa is also a bona fide culinary genius. She’s an expert at cooking and she’s always ready to teach Dina something new.