Baby 1 1 month has no teeth.
Could be calcium deficiency. Brand? All the same. It is recommended to use calcium lactate, not to eat it with milk at the same time, which will affect absorption. To take cod liver oil together, the current dose is less than one year old, and it is suitable for one-year-old children after one year old, and then take it. Get more sunshine. Or take calcium zinc gluconate oral liquid and supplement zinc by the way.