Wah, susah jugak nak cari florentine low-sugar version kan! A few of us mums tried reducing gula dalam regular florentine recipe tapi texture jadi lembik, kena pakai honey atau dates paste instead kalau nak something naturally sweet, mix dengan butter and almonds/hazelnuts, then bake sampai golden. Honestly, at that age mungkin lebih senang nak adjust existing adult recipe by cutting down sugar drastically (try pakai 1/4 lang of original amount) or just make basic almond biscuits without the caramel topping dulu, then boleh add the florentine part later kalau dah bigger? Kalau boleh try posting in the group with a screenshot of the recipe you found, sure ada mum yang ada tried-and-tested version!