Panel 1: We find ourselves in a change room at Philpotts today. As one would have every right to expect, this is so we can see Elly filled with rage because the pair of jeans she's trying on make her think that she looks like a baked potato in denim.
Panel 2: Next, we see her glaring angrily at her reflection while wearing a more formal outfit that doesn't look good on her because she cannot love what she sees in the mirror.
Panel 3: When she tries on a third outfit, we have every right to expect her to either yell "AAAAAAAAAACK!!!!" in rage or thought-bubble that she's wearing a potato sack.
Panel 4 She almost admits that she has a character defect that she needs to jettison when she tells herself that she should never shop for clothes when she's in the fat mood that started when she first understood what reflections are and will end when she dies.
Summary: It's almost a blessing that this turns into "MY HORRIBLE SON IS HIDING THIS GIRL FROM ME!!!" instead of "I won't admit that my imaginary pot belly is the end product of slouching forward all the damned time" because I'd rather have Elly project her own habit of making oops babies onto Martha than blathering about a jenked-up body image.