Taking on second pup

[thinkingaboutfostering]

My lab bitch is now seven months old and doing very well. Training is going well and we are enjoying life together. I had her from some friends who live about 4 hours away. Another mutual friend (let's call her Ann) also took on a pup from the same litter and she lives not too far from me. We went together to pick up our pups and bring them home and we met up for a walks and the dogs get on well. Sadly Ann found out a few weeks ago that she is seriously ill possibly terminally. She has now accepted that she won't be able to cope with a bouncy puppy and has decided to rehome her. Naturally the breeders of the puppies have offered to have the puppy back however they are a bit concerned as they kept two puppies themselves and they probably would not be able to keep the puppy long term. So would have another move in the future.
The other issue is the distance between the breeders and Ann. If the puppy were to return to the breeders then the odds are Ann won't see her again and whilst she accepts that she can't care for the puppy I think the idea of never seeing her again is a trauma too far right now.
I had planned on getting a second dog but was planning on waiting until my pup was a bit older before looking and then would get another pup.
Obviously it had never entered into my head about having one of my pups siblings as this is a totally unexpected situation. My heart says take the puppy. Ann will still be able to see her. The dogs get along well and always have done Ann's pup has stayed with me several times in the past couple of months and there have never been any problems.
Would I be insane to take her on?
Is it likely to adversely affect my own pups training?

[tabulahrasa]

"Is it likely to adversely affect my own pups training?"

Unless you put in lots of effort, yes.

They'll need training and walking both together and separately to make sure they're both bonded to you and not to each other.

You'll have two teenagers at once, which might be fine, it might be awful...

Normally it's advisable to wait until your puppy is an adult before getting another, but, I can see why you're tempted tbh.

[Jenda]

If you are experienced with dogs and feel confident then It would be a lovely thing to do- for both dogs, you and Ann. But don't beat yourself up if you decide not to, it is a lot to take on.