My 6month old baby's leg's joint got little cracking sound. it is normal? She seems normal. Is it lack of calcium or any nutrition?

Hi, the cracking sound is normal as it happened to my friend's baby too. There's no cause to be alarmed if baby is not crying loudly in pain or can't move their legs. The reason is that babies/toddlers joints are very very loose because their continous growth, meaning to be able to grow and stretch they are loose where the cartilage is. It will get better when they grow older. Hope this helps.