I didn't consider Vaporeon with belly expansion before! Could be a viable path for her.
There's a lot of hype for the first three Eevee evolutions triplets and I would want to design them better if possible. Perhaps I'll open a discussion for ideas about their growth paths and behaviors.
About the breeding part, I'm not sure if you're talking about pregnancy/egg-laid or just simply breast feed, as almost all the girls have breast feed. For the previous, I'm going to add them as additional story/scenes in the long future, but it's not my main focus for now.