I wasn’t sure how young to go but they look like around 8ish?
Linako was always a girly girl who loved to dress up and roleplay as princess or alice in wonderland. She was the type who would call “mother” in house before playtime started. She would use an EZbake oven and pretend teatime with anyone who was available.
Fuki was a wild child because I honestly believe she was raised by animals or something before she came to the Sonone house. She howled and jumped on things and liked to roll around in the grass and mud. Not like it has changed much since then.
Natsuki was a…plain kid, plain personality, plain grades, plain everything. He would be laughed at by others but the kid would think he was actually being interesting. As a youngin’ he really liked watching DIY shows and developed a habit of fiddling around with different hobbies. A bit gullible.
Remu was very into superhero shows and liked to help others cause he thought it would take him to the ranks of Ultraman. He was really protective of Linako when she was a baby; overall he was a sweet kid. Said “eyahhhhhhhhhhhh” a lot when frustrated though.
On the quiet side yet has a lot of interesting things to say? (A charming dollface in a sundress type.)