The dress is so tight, no belt needed. hmmm
Wait ... it’s all becoming clearer now ... the white dress with black polka dots, the white skirt up under her bust line ...
She is gaining weight right around her waist. She has not replaced some of those clothes, probably because she can’t admit she’s going up a size or two. (*Ahem. I speak from experience. I know that look :-/ )
Gaining weight around the middle — either stress or PG.
They have they money, they can get her clothes altered and-or buy a full length mirror for the family quarters.