If your niece is just using Snapchat for fun features like puppy filters and not connecting with others, it can be relatively safe—as long as strict privacy settings are in place. You can turn off friend requests, disable chat, and limit who can view her stories. That said, Snapchat is designed for teens and adults, so even with restrictions, it’s good to supervise use and check settings regularly. For kids, filtered camera apps with no social features might be a safer alternative.