Yes it's happened to us.
We have 5DC and I often get asked if I'm a childminder,I look to young (according to people that don't know me)to have 5 children,I hate when people assume I must have been a really young child when I first got pregnant(I was 21)I'm 38 now.But I take it as a compliment,nearly 40 and people still think I'm in my early 20's so I can't really complain.
I get asked quite a lot about how we cope and people do make assumptions about what your house must look like,ours is always clean and tidy,that surprises people that don't know us.I just take that as showing how well were doing.
People tend to make assumptions about your finances as well and think your children must go without,ours don't they go on holiday every year,they do out of school activity's,they all have nice clothes and shoe's,lots of toys and books and the oldest 3 all have phone's and they all have handheld game consoles.They all get they're hair cut in an expensive salon.They get to go on all the school trips including the one's abroad.We have savings and we've saved money for each of our children.
Honestly we've usually always get positive comments when were out.
People tend to do a sharp intake of breath when we walk into a restaurant(usually older couples or people with one or two children are the worst)they seem to think because we have 5 children that we'll be loud and that the children will run around the place,were never loud and they're always really well behaved.Older people usually come up and tell us what a lovely family we have and how proud we must be ect.
Couples with less children usually just go quiet when they're own children start running around the place making a lot of noise or point us out to they're children and say look how good all those children are being.
Some women presume because I go out with make-up on,hair done,nice clothes on that my children won't be as well cared for(they've obviously never heard of multi tasking)
they soon go quiet when they see that the children all look immaculate and that the girls have they're hair all styled.
Negative comments (the one's that are challenging how well your doing)
are usually made by people that are jealous so I'd take them with a large pinch of salt.