...then it is only polite to assume the woman with the toddler is the mother and not the grandmother!!!! I am 42, DD is 20 months. No, I honestly don't look a lot older!! I know that there are plenty of grandmothers the same age as me, but there are loads of older mothers around too. If in doubt, please be nice and assume I am the mother, or just say nothing at all!! It often seems to be the older generation (60+), who look at me questioningly "Is she your granddaughter?" or "Spending time with your...[querying look]...grandchild?"
And breathe...