Getting a Caesarean section is much more likely for people who have already had one, though it is by no means a certain thing. The chances may be higher, but that is usually because a woman is scared into thinking that she can not attempt a vaginal birth if she has already had a Caesarean. The truth is often that the doctor recommends a Caesarean to make his own job easier and not because there is a medical need.
There is a very small chance of a uterine tear for women attempting a vaginal birth after a Caesarean (VBAC), but the chance of a tear is lower than the chances of having some type of complication with a Caesarean. Infections after a Caesarean are common, as are injuries to the baby and maternal hemorrhaging. The fact that there is a small chance of a tear should be carefully considered before attempting a VBAC, but the chance of Caesarean complications should be equally considered before an informed decision can be made.
Before making the decision, also consider the lengthy recovery time that will be necessary after a Caesarean as compared to the relatively short time after a vaginal birth. The recovery time is especially important if the mother has another young child at home to take care of. Whether you choose to attempt a VBAC or concede to a repeat Caesarean section, be sure that you have the final say unless there are mitigating medical circumstances that make a Caesarean the better choice.