Oh, you can tell. When the toddler is kicking off and screaming like a hogtied pterodactyl? You know *THAT* look. That look that says "Get your kid under control" as I'm trying to get him back into his stroller and he's pretending that he's a starfish with rigor while screaming ... The "helpful" comments as I'm trying to keep him under control as his sister is taking part in her science fair. Nooone ever approaches the mum with the tantruming toddler to offer FRIENDLY help - in fact it's like a fallout zone of silence around us... and only those with grudges to bear enter.
I've been at this single parenting thing for a year now which granted isn't long in the grand scheme of things, but I have been on the receiving end of those looks, and tuts, and comments - and I don't want to feel like that on vacation, I want happy times!