Why are some black people are rude to skinny/short mothers?

I am a 24 year old black mother with a 3 month old daughter and I don’t understand why lots of black people are very rude to me by being a skinny and short mom, (I’m 5’0) and I have a normal fast metabolism (I’m 102 pounds), I sometimes start to feel less of a mother because I’m not thick or big enough to be a mother, I get dirty looks from family members that are mothers who are bigger and taller than me and I’ve seen other short and skinny black mothers so I’m definitely not the only one, so I was wondering why do some black people are so rude to skinny and short mothers?
Why are some black people are rude to skinny/short mothers?
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