With Cash I also doubled his 12 week weight, but he ended up bigger than that. He was 1.7kg at 12 weeks, but is more than 5kg fully grown. When he was a year old, he was about 4kg, but he was very, very skinny. So now, at 3 years, he is 5kg and very healthy.
Sorry for the metric, I don't have the time to convert to lbs.
