Every relative who visits lifts our daughter for two seconds and announces she's 'too light'

She's eight months old, feeds well, crawls into every corner of the flat and sits right where she should on the growth chart our paediatrician keeps. Nobody who says 'too light' has seen that chart. Nobody has weighed her either. They lift her, frown, and suggest ghee in everything. I'm a doctor and I still end up explaining percentiles to an aunt at the dining table, which goes nowhere. My partner nods and changes the subject. Is there a reply that ends this without starting a bigger conversation? Third visit this month.