My DD was 7.2 at 8months and is about to have another weigh next week. I'm thinking she'll be between the 8-9ish mark now She's always been on the smaller side but always in proportion with visable growth. She even has some little fat rolls You would know in yourself whether or not there is reason for concern.

FWIW i get the 'oh she's so small' and 'oh she's so light' comments all the time too