Daughter looks like she isn’t ours

I am so sad over this. My daughter is blonde hair blue eyed. My husband and our son all have brown hair and brown eyes. Every single time we go out as a family, people point out how she doesn’t look like us. I get lots of “switched at birth” and “milkman” jokes said to me, and it just makes me feel like shit. It’s like everyone thinks I cheated on my husband because she doesn’t look like us. I always just say “yup it’s from her grandparents!” Because blonde hair blue eyes is on both sides. Even my husbands sister asked if I’m sure she is his daughter! Sometimes I feel like paying $200 for a dna test just so they will all stop questioning me, and more importantly her. And also maybe sending them all back to middle school so they can learn about recessive genes. Anyway I’m just ranting. Anyone else here go through this??