My birthday present from the cactus

I bought a cactus about 10 years ago. She had lots of pups and has given me many many plants but this year was the first time I have ever seen one flower. About 3 months before I was excited to see little buds appear which got bigger and bigger and bigger again. They finally opened on my birthday and measured 26cm (10 inches) rather dwarfing the cactus body! They wilted the following day so I felt rather blessed.