Boris is Ben and Didi's father, grandfather to Tommy and Dil. He, like his long-time wife Minka, comes from the "Old Country", so he says. This place was later revealed to be Russia. He always talks about how horrible life was in the old country however Didi once revealed that he actually comes from a very well off family. She then added "He wouldn't know a goat if it bit him in the face". He frequently gets into petty arguments with Minka over various issues, such as who will turn on the television, and why chocolate cake should be used at birthday parties, instead of carrot cake. He is also a wonderful storyteller, as he would often tell vivid stories about "monsters". He and Grandpa Lou are a lot a like in story-telling, their overactive imaginations with their stories, and where romantic with their wives. As seen in "Toys In the Attic" he whispers to Tommy that he found Minka to be the most beautiful girl in the village and adores her cooking. Being Jewish, Boris and Minka embrace their religion well, sharing their faith with their extended family, including Angelica whom he also sees as his own grandchild. This is very evident in "A Rugrats Chanukah", when he sees Angelica crying, he carefully takes her from Schlomo and continues to hold and comforting her until she calms down. Its also shown in "Toys In the Attic" that he and Minka keep various knick-knacks and antiques, most of which are broken by Tommy and Angelica. After which, they both faint but later they hide all the antiques from the kids. He is seen in Rugrats Movie, giving a goat for goat's milk to Didi when she's expecting Dil soon. And also helping Lou look after the babies when she goes into labor. He's seen in beginning and end of the Rugrats In Paris: The Movie, getting hit with cake by accident. Upon hearing Lou laugh at him, he starts the food fight by hitting him with cake. He's seen in All Grown Up, in "Blind Man's Bluff" being taken to a water park. However its only because his grandchildren wanted to go on rides rather than spend time with him. They soon discover they lost him and go all over looking for him. However, Boris is shown to be fine and in fact had fun, he then adds he didn't like being treated like a child. To which the kids apologize for how things where and enjoy the rest of the day with him.