I've heard multiple people doing this with Cashu: set up mint running on your own node, mint ecash for your kids and let them use it as a lightning wallet :) nostr:nevent1qgsxwr42cjdv44uy2jkc8c6yx0n95fkg3r9y20fg4yf9nn7tafq9rjcpzamhxue69uhhyetvv9ujumn0wd68ytnzv9hxgtcpzamhxue69uhhyetvv9ujumn0wd68ytnzv9hxgtcqyruhn5ahpmwku6cymkntr5ex8ww3ez5zsg5y6u39s64ly6ndxj3auw20ks7