FFVIII - How to know Laguna is Squall's father?

"Though it is never directly stated, it is heavily implied that Laguna is Squall's father. When Laguna left Winhill Raine was pregnant, and the baby and Ellone were taken to Edea's orphanage, which is where Squall grew up. Additionally, it is stated that Moombas can recognize people forever after having tasted or licked their blood - Squall being Laguna's son would explain why the Moombas in the prison chant "Laguna" upon meeting him. Laguna also always shares Squall's stats during the flashback sequences, and also carries Squall's Triple Triad card. Ward and Kiros seem to be aware of their relationship: if they are spoken to aboard the Ragnarok at the end of the game, Ward tells Squall he should be glad he does not resemble his father, and Kiros states he resembles his mother, indicating the two of them know Squall's parents. "