Ahahah, I think this answer was worth waiting for 4 years) But if suddenly someone else is interested in this question, here's what they write in the databook:
"According to rough estimates, Jin is just over 32 years old, because he became a Hunter at the age of 12, and then married Gon's mother at the age of 20. When Ghosn was 2 years old, Jin gave him to Mito Frix"
Oh, well, I can't. Killua and Gon are such kids here. It resembles a scene on the playground "Hello! I'm Gon." "And I'm Killua" "Let's be friends?" "Come on" Just cuties
But if suddenly someone else is interested in this question, here's what they write in the databook:
"According to rough estimates, Jin is just over 32 years old, because he became a Hunter at the age of 12, and then married Gon's mother at the age of 20. When Ghosn was 2 years old, Jin gave him to Mito Frix"