Nah, I'm a much shittier mum than that. When DS2 was about 5 months old we went on holiday to the Isle of Wight and visited the theme park at Blackgang Chine.
I sometimes suffer from dizzy spells* and was having one of my 'funny turns' on this day. I'd let DS1 cajole me to go on some little spinning ride - I shouldn't have, because I unsurprisingly felt even weirder afterwards.
DP had been carrying DS2 who was asleep and when we got to the slide he said "I've just popped him in the buggy, you do the straps, me and DS1 are going on this big slide" and promptly buggered off.
I looked at DS2 and he was, I thought, fast asleep. I felt an immediate hot flush and thought I'd have time to whip my coat off, because I thought if I don't I'm going to go over.
But I'm a clumsy doofus anyway and this is compounded when I go weird. I was so busy incompetently struggling with my coat and trying not to fall over, I didn't register that the people calling "oi love, the baby's slipping out the pram!" we're talking to me until it was too late, and DS2 slowly and gracefully slid down between the seat and the solid bar at the front of the pushchair.
His descent was thankfully gentle and he ended up sitting on his bottom on the ground, completely unharmed, looking up at me like 
Although I did hear the people, they sounded far away and everything went a bit 'grey' - I don't know how else to describe it, but it's how I feel if I'm about to pass out. It's rare for me to have a turn that bad though, just my luck it happened out in public and not at home.
I developed an obsession with checking and re-checking the buggy straps after that!
*Before anyone says "go to the doctor" about the dizzy spells - I have, lots of times, always get sent for bloods which come back normal. I've given up and the episodes have been fewer and less powerful lately. Also the hot flush I get with a dizzy spell isn't meno either, because I've been checked for that too.