The process analysis is as follows:

She was 8 years old in 2008, so she should have been born in 2008 -8=2000.

But why have you only had two birthdays after eight years?

We know that 2000 is a leap year, and only February is the most special month, so Xiaohong must have been born in February.

As long as you find Xiaohong in the leap year, you can celebrate your birthday!

2004 is a leap year, and February has 29 days.

2008 is a leap year, and February has 29 days.

Just had two birthdays.