I got the same comments about my ds even though his weight was always on par with his height according to the percentile charts (always around 98th for both.)

When he was 7 months old I actually had a paediatrition in the Childrens hospital say "this is where obese toddlers come from" to a group of students he was trying to impress. I took great offense and picked him up on it and embarrased him!