Don't see the facial similarity, but you're cooking with the similarity between Yuni's mom and Nanase.
Both are too busy to spend much time with Yuni, who is lonely while she waits for them.
I know I'm reading into this too much, but I saw parallels with the exchange about eating pancakes
Another clear parallel (maybe foreshadow) is Yuni's mom telling her not to fall for someone that priotizes themselves (like Nanase), implying that's the reason why she's divorced.
Prediction time: Yuni is gonna bring home Fuuko and mom is gonna assume she's her girlfriend, while Nanase is the mistress.