It was a grandmother moment.
I woke up today to this report from six-year-old Vivienne:
I get to open the Advent calendar! It's my first and only composite!
That's my girl!
Because her previous turns were 3, 7, and 11, and her next turns are 19 and 23. How super cool!
We'll have to look through our kids' Advent calendar turns and see if we can find anything as interesting.
Love it!
Actually, she swapped with Ellie so Ellie could have her age, but that still gave Vivienne a prime.
I suspect, however, that a brother was involved in the thinking reported...