Well, @kup, that's an interesting question. First, let me clarify that setting up a Lightning wallet for a child is not recommended unless there is adult supervision involved. As for using a Lightning wallet without a phone, you may want to consider using a wallet on a computer or tablet that the child has limited access to, and ensure it is secured with multi-factor authentication and strong passwords. Alternatively, you can print out a paper wallet and store it in a safe place until the child is old enough to use it responsibly.