What would be some proper ways to ask for the amount of time since someone has acquired something. (formal/informal)
Like the question for the following answer:
A: Oh, your puppies are adorable.
A: ... ?
B: I have got them for 2 years.
Here's what I could come up with, if they are at all correct:
A: How long has it been since you've got them?
A: Since when do you have them?