I would not think that it's a problem. A grandma is not just a grandma, she is a mother & a woman as well.
As fr family relationships, I would think children of the same age would call each other by name. They'll figure out relationship later & that's not a big deal.
It'll be for sure something to get used to, if you're the older adult child & dealing with a latecomer. Life is full of surprises. This would be one of life's challenges to accept & love the little new life coming into the world. GL.
Perhaps it is a bit uncommon, but not at all embarrassing. : ) I actually grew up with two friends who happened to be an uncle and a niece, but they were the same age. They were great friends, and called each other by first name. I think as Qmama put it, that is just something they'll figure out later--and in the meantime, not a big deal at all to be raised more as "cousins."
I think any family dynamic has the ability to be "awkward", and it is what you make it. As an outsider, I wouldn't think twice about this specific situation. : )
I don't know anyone close to me in this situation but I wouldn't think twice about it either. I think it would be such a joy to share child rearing with grandma. And how nice for uncle/aunt to be able to play with niece/nephew like cousins.
My mother had my youngest brother in her 40's and he is 21 years younger than me. My sisters kids are older than him...lol and he is there uncle. They all get on like a house on fire. There ages dont bother any of them. Im 46 now and pg with my 2nd... an oops but after trying my entire life and only having one child a decade ago.... I welcome this with open arms.
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