hi, i have just recently been searching my family tree and have noticed you are lookng for Charles Rounds(1836-1883) and frances pickering's nameless children. According to what I have read there is two other children they had...that is Agnes Rounds and David Rounds. You can find this info if you type in Rounds Family Tree fiji as i descend from their child Charles Rounds(b.1858) who married Esther Helena Ryder who had 9 children in which their son Isacc Rounds(1882-1931) married Jessie Bennion(??) and they had 10 children in which their daughter Maria rounds is my great grandmother.
I'm not sure if I can help you however if you check out the fiji Rounds family tree and are able to access it, it might be of some help to you.