My mom had suspicions that something was wrong before my first birthday... I had skin issues when she was breastfeeding me, and later she knew I couldn't tolerate a plain egg, for example, but it was certainly confirmed when she made me an angel food cake for my birthday.
So, 30+ years later, and I'm still allergic to them. And some other stuff, too, but the eggs are certainly the biggest challenge. I can't handle even trace amounts, so going to restaurants, eating bakery bread, etc, is always fraught with danger.
I have a few (ok, lots of) egg-free recipes in my collection, and I rarely use the commercial replacers. I love to bake, when I can find the time.