I'm in the US and I don't think it's typical to give gifts upon announcement either.
However, with that being said, How sweet of you! I would have been delighted if anyone had thought it was special enough to get me a gift. If you want to get her something, I am a fan of gifts that are for mama. Baby will get plenty of stuff she'll want and need, but Sometimes the focus is automatically only on baby and mama still needs pampered too. Bath oils, Candles, etc.
AND with THAT being said, best gift sometimes at 6 weeks can be help. If she's sick and blah, making some freezer dinners or something might be helpful. If it's not her first, babysitting is a great help. Things like that. Do her dishes. Stuff like that is nice
I'm sure she'd love nothing better than for you just to spend an afternoon with her! Grab lunch, and go baby stuff shopping, she's probably so excited she'd love to spend the day talking to her sweet sister about it all!
I think it can be seen as bad luck to buy anything for the bubba until the 'danger phase' has passed, so if you do get her something I'd recommend it is something for her... I think I'd love to be given a voucher for a massage or a facial, but I love the suggestion of an afternoon together talking baby talk and shopping for baby stuff!
It's not customary to give gifts upon announcement but that doesn't mean you can't. Just don't go overboard. Something thoughtful would be nice like a book about pregnancy, slippers, or anything you think might make the mama more comfortable. Do be aware though that early pregnancy can be a very traumatic time if the mother is experiencing problems like bleeding or MC. Getting a gift now might bite you later if something goes wrong by making the mom feel worse. Just something to think about.
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