That’s awesome!! Bet the parents are beautiful.
And aww that’s awesome!! That’s similar to what DB & SIL did.
They adopted Franklin last September when Libby was only about 9 or 10 months old (I think her birthday is either November or December, not sure) and Franklin was only about 4 months old I think (around 16 or 17 weeks). So they are very close in age. Libby is now almost 2 and Franklin turned a year old in June.
They are best friends. They’re also male and female too though which may help but I think they just love having a friend.
Libby LOVES everyone and anyone so I think she was very much wanting a dog friend to play with and was very glad when she finally got one.

it helped calm her down too cause she used to get VERY excited when she saw other dogs and now she has her own permanent best friend
And Franklin was very anxious and scared when he first came to them and having such a loving, confident big sister has really helped him come out of his shell.
I don’t think I would ever have just one dog after seeing how much they love each other and how good they are for each other.
But it has to be the right match. I’be seen some people with younger or more energetic dogs who constantly harass and bully the older and/or more mellow one, wanting to play all the time or very pushy, jealous, dominant, etc. or whatever and I don’t think that’s fair either letting one get bullied every day.
I think getting similar aged dogs is an excellent idea but I do think the only should be slightly older and trained first rather than adopting, say, litter mates at the same time. Training two very young puppies at once is hard.