@.access:
I will assume Perospero is 50 too because that will mean Linlin became a mother at 18. I doubt Oda would go for underage pregnancy.
At least one child every single year. Katakuri/Oven/Daifuku = 48 years old. So there's two options. 1. Perospero and Compote are twins and they are both 49 years old (which make Anana 7 years old). 2. Perospero is 50 years old and Compote is 49 years old (which make Anana 8 years old).