Is an increased appetite but no morning sickness also common in pregnancy?

My sister is 6 months pregnant and she's eating much more than before. She rarely had cramps, no morning sickness ever, no swollen feet, no vomiting. But she's eating a lot that it worries us. She doesn't just craves chocolate and sweets but also more food.

She has gained slightly over 20 Ibs by now. Basically she had a practically comfortable pregnancy so far with the only change in her increased appetite. Is this also common? No sickness nor nothing, just her wanting to eat more.

Is an increased appetite but no morning sickness also common in pregnancy?
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