LO losing weight at 11 months

Hi mommies, just a concern... Though the sister at the clinic told me that I must not worry now, I am. Well, last month when my baby was 10 months, she weighed 8.04kg. Then I took her to be weighed again 5 days and she dropped to 7.7 kgs. But she has never been sick, she's very active. She also eats solids now 3 x a day and even has her biscuits for snacks with her milk. She also doesn't have abloated tummy or anything like that. The sister told me that it could be just, she metabolizes fast. And it's true. she makes a wee a lot and makes a poo twice a day. She said I must bring my LO again after two weeks. Can anybody share anything or a point of view on this? The sister said if my LO's weight next week will be abnormal still, I wmust see the pedia.

Thanks in advance.