Ellie O'Reilly

Ellie is the youngest O'Reilly child, being a few minutes younger than her twin sister Ella. They are the younger sisters of Fiona (and four unnamed brothers) and daughters to Riona.

Despite them being identical twins and thus almost indistinguishable physically, they are distinct in their personalities. Ellie is the more romantic of the two, saving herself up for someone special (not necessarily marriage but she doesn't just wanna "do it" at the first opportunity like Ella wants.) She is also the slightly more cautious of the two although Ella gets her into plenty of mischief anyhow.

There is a slight confusion regarding their age. The first time the appear, they greet the protagonist with "Daddy" (as Fiona had tricked them that he would get together with their mom), the protagonist jokingly protested that they weren't his and Riona then laughed and said that he would have had to have been around two when they were born. That would but them at 19. However, the Part 2 and later relationship-bios specify that they are 21, the same age as the protagonist. Ellie also at one point says that she has waited 21 years for that special first kiss, further indicating that this is the right age. Perhaps Riona didn't know how old the protagonist really is and overestimated slightly due to his height and maturity. (Personality-wise however, the twins behave much more like the younger girls like Sophia or Isabella than like the protagonist.)