That's one of the best stories I've heard in a long time! Your mom knows what she's talking about; she seems like a brave woman. She's completely right; people have to take more leaps and leave their comfort zone more often. Too bad that most parents teach their kids the opposite, which resulted in this whole generation of scared and lost millennials.
I have a similar story; I remember that my dad used to take me swimming in summer at the lake, even if I was a kid. The water wasn't ice-cold but, it was still cold enough for a 3-4 years old kid. Those experience helped me never to fear water thus, I learned swimming at a very young age.