It is difficult to give you a definite answer without knowing the birth weights of each twin and also their present lengths (heights) Your 'older' twin grandson may simply be a much bigger baby than his brother. His weight of 7.5 kg places him on the 90th percentile line of the infant growth chart, while his brother's weight of 6.4 kg is exactly on the average weight line for his age. This would be unusual if they are identical twins, but I presume that they are non-identical twins. Their feeds are the same and Lactogen is a good formula. They do not need water or rooibos at this stage and you can start to give them a little water when they are 6 months. They both appear to have virus chest infection now and it is a pity that they were given antibiotics which do not help for virus infections. You cannot reduce either twins milk intake now, so just continue feeding them as you have been doing.
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