Is this dear sisters or dear friends? I remember she came to the door in dear sisters. Nadeshiko called her "Himako". I thought that was very cute. All of the Oomuro sisters have names ending in "ko": "Nadeshiko", "Sakurako", "Hanako". By calling her "Himako" Nadeshiko included Himawari in the group of sisters, seemingly as an honorary sister of the family.
Wow, I didn't notice it, that's so kind of her — seems gonna rewatch to check it. Picture from "Dear friends" as I remember.
These films showed a completely different side of Himawari and Sakurako's relationship. When I started reviewing season 1, I was not used to seeing them arguing with each other (tsundere-like) in the first episodes. In the spin-off, I remember only one moment where they showed the tsundere side — when Himawari came to the Oomuro family and was upset when she found out that Sakurako couldn't meet her (she was in the shower as remeber), but then immediately realized: "It's not like I came just for her (>//<)". The rest of the time they look like... normal, or kind of that, I guess, friends.
