Like many things in medicine we do not know the exact cause of Club feet(Congenital Talipes Equino Varus - CTEV). I am sure you would have got karyotyping done for this child also and if you have not done so far ask your paediatrician whether it is required and if there are any other abnormalities in the child. If there are none, (as is most likely) the child will have an excellent chance of a full recovery and a normal life. Of course the child will need care of an expert paediatric orthopaedic surgeon. Repeated casts and surgery if and when required is the right treatment. There is nothing that is 100% in medicine so to ask if it 100% curable is difficult to answer but with good treatment it should be nearly that.
If there are no abnormalities and the karyotyping is normal there is a 2-8
percent chance of recurrence in a subsequent child (from various published
series). There is always another way to look at statistics and though 2-8
percent recurrence is a very high risk it also means that 92-98 percent
chance is that the baby would not have a CTEV. Please be assured that it is
unlikely to occur again but if it does it is certainly treatable condition.