2001 forester

My mother just found out she needs both rear axle bearings replaced on her forester. This car only has a little over 100,000 miles on it . This seems a bit odd to me to already have problems like this but she just had all her fluids changed a little over a month ago and then this happened is this just a coincidence? Just wondering if anyone else has head a problem like this. Thanks for any help.:banghead::banghead: