My bb has the same problem. She's now 6.5 months and weighs only 6.5 kg.
She started to hate milk when she was 3 months and I gave her rice cereal. Starting from 5 months, I gave her congee with carrot, fish and veggies. She can only have 10 oz of milk every day (2-3 oz every time). She is very small but she is active and looks healthy. I guess there's no problem.
My baby just on 10% growth line also la.How can I do?? He can drink 30 oz milk per day ka la. Not sleep at daytime but have about 10-12 hrs sleep at night time.